Artillery: News & Discussion

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niran
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Re: Artillery Discussion Thread

Post by niran »

brar_w wrote:^ This can be seen in the video below.
in the video the one pulling firing lever also load up the charge inspect and clean (good man he is) gun master is reading out the figures for 2 burly men pulling the wheels to position. Gun master remain on front of he gun besides the barrel (not a good place to be) if a burst occurs he is gone for good.
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Re: Artillery Discussion Thread

Post by Singha »

with 10 men milling around, any explosion has a good chance of affecting one or two, this is where the heavier guns score in degree of automation and crew safety esp the truck mounted & SP tracked ones.
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Re: Artillery Discussion Thread

Post by Singha »

Saurav Jha‏ @SJha1618 14h14 hours ago

The double standards that come into play whenever an issue with any fancy imported weapon system crops us makes me want to puke.

Saurav Jha‏ @SJha1618 12h12 hours ago

Don't be surprised if some start calling for the import of 'match grade' US ammo for the M-777, along with PGK kits.

Every imported system has an eco-system of backers who immediately activate their talkathon contacts the moment an issue crops up.
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Re: Artillery Discussion Thread

Post by jamwal »

Did the barrel actually burst and ammunition exited from sides as well ? Or the shell disintegrated in barrel but exited only from the muzzel ?
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Re: Artillery Discussion Thread

Post by Singha »

per the report shell burst inside barrel and exited in several pieces. no barrel burst hence no injury to anyone. would have damaged the muzzle brake ofcourse.
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Re: Artillery Discussion Thread

Post by Austin »

I suspect every gun barrel and every gun shell made would have some defect piece ( inspite of all the QA/QC etc ) after making lakhs of round it is about probability ,There wont be any thing like 100 % defect free barrel ammo gun missile etc .....it is just a question of when one encounter this situation and not if.

Sometimes it would just be bad handling , improper storage./logistics handling that would make a shell defective and something that will go unnoticed
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Re: Artillery Discussion Thread

Post by Singha »

imo if a barrel or breech burst occurs it is generally flaw in gun.
if the barrel is intact but the shell bursts inside it is fault of shell.

once the charge ignites and expands to pump out the shell , the guns role is mostly over other than ejecting the gases and unburned residue and making sure the barrel does not burst.

being a manual loading system in trials, the chamber and barrel would be clean and checked .

so this imo is a ammo problem and not related to 25liter chamber higher charge as the chamber here is normal size.

not to say only desi ammo has problems, but unless we get details of previous M777 accident reports we dont know if american ammo was also at fault earlier and HOW these are identified and rectified. with both US army and BAE helping out, I dont doubt the RCS will be quick.

if there are or manufacturing or QC failures in OFB line, this is a good opportunity to fix it with BAE and american help 8) will benefit the other guns also using the common ammo.
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Re: Artillery Discussion Thread

Post by nvishal »

The OFB munitions making factories look something like this:



These are cottage industries with no standard practices and quality check.

Look at the way they pour powder into the brass. It's very uneven. This is likely how OFB does it's powder allocation. It's obvious that each shell will have a different combustion power.

All this is guess but this is the most likely.
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Re: Artillery Discussion Thread

Post by Philip »

If it was desi OFB ammo,and found to be due to defective ammo,then a thorough cleansing of that Augean stable is reqd. The OFB has bene castigated time and again by the CAG and appears to be an "untouchable" DPSU,where it is never held to task,or any of its heads for serious deficiencies which have cost the country thousands of crores worth of useless ammo,etc.,etc. Now wiht both desi bofors/Dhanush and the BAe light howitzer suffering barrel bursts using desi ammo (as it appears for both) the new DM NS must get her act together asap reg. this extremely serious incident.Our entire arty capability in the mountains heavily depends upon the success of this LW gun,being bought from abroad at huge cost.
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Re: Artillery Discussion Thread

Post by Austin »

Singha wrote:imo if a barrel or breech burst occurs it is generally flaw in gun.
if the barrel is intact but the shell bursts inside it is fault of shell.
There is a design flaw , manufacturing flaw and then other flaws involved in storing , transportation logistc etc ......Manufacturing it self is not full proof else we wont have seen barrel burst or ammo burst from America , EU etc where we want to believe QC/QA are the best in industry and practised religiously.

Even weapons after x amount of manuf ( that could be lakhs or millions ) will encounter this flow inspite of all the strict control thats the inherent nature of the game called probability .....No one can gurantee 100 % full proof system.....even rifles have issue with barrel and ammo.

if there are or manufacturing or QC failures in OFB line, this is a good opportunity to fix it with BAE and american help 8) will benefit the other guns also using the common ammo.
The question is IF its a manuf flaw, but what if this was an issue with shell wrt to storage transportation handling etc something breach that could have gone undetected ?
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Re: Artillery Discussion Thread

Post by negi »

M777 vs the OFB , round#1 score :0-1 . An unstoppable force has met an 'immovable' object take that you Americans :)

On a serious note assuming DDM report about M777 trials being done using OFB shells is true one thing is very very clear i.e. it won't matter what gun we buy because guns are useless without ammo ; so the LCD here is the OFB and we will have to live with it after all the ugly truth is all our existing ammo stockpile is from the OFB we cannot runaway from this nor can someone discard all our existing stockpile and replace them with match grade ammo via imports . Point being we have no choice but to build in a buffer number for guns which we should be ready to sacrifice on a per year basis due to faulty shells , it also implies we might end up putting lives of our men at risk during such failures . We will continue to pay the price until something fundamental changes with the way we make 155 mm shells .

It would be interesting to find out the batch number and manufacturing date of shells being used by M777 and Dhanush during the trials , I mean if these are old shells perhaps it makes sense to replace all our old inventory of shells on a war footing. I think a look at entire manufacturing line and tightening up the tolerances and processes at every step can alone reduce the number of bad shells being produced per 'n'.

On foreign vs Indian , the comedy circus will start when orders will be placed in volume and BAE will be asked to provide ToT to OFB , when guns from that lot will fail BAE will wash it's hands and point to OFB's incompetence :)
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Re: Artillery Discussion Thread

Post by Pratyush »

It seems that arty procurement is fully jinxed. That every gun under tests has faced some or the other issue.

ATAGS has been the exception till this time. Let's hope that the run of luck holds.
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Re: Artillery Discussion Thread

Post by Austin »

M777 is a good gun and right now only available , every gun in their life will experience a barrel burst or shell explosion or both , Show me one gun which did not including our own , Its like saying an aircraft should not crash at all during its life time ...heck we had a Jag exploding in mid air because of a fulty bomb that triggered in mid air and lost the aircraft.

We dont know yet if its faulty Ammo from OFB or fault in handling logistic storing of ammo which caused the ammo to develop issue that went undetected and lead to explosion , chances are we will never find it out and OFB would be made a convenient scapegoat in the whole affair.
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Re: Artillery Discussion Thread

Post by brar_w »

Singha wrote:with 10 men milling around, any explosion has a good chance of affecting one or two, this is where the heavier guns score in degree of automation and crew safety esp the truck mounted & SP tracked ones.
Correct, and this is a cost of being able to take the weapon to places where the heavier, more automated systems can't go. Perhaps with further breakthroughs in materials, the next generation of ULHs can offer more automation within the same weight margins. On the current systems, I guess the right question to ask may be, what can be done if say the weight threshold was increased by 500-600 kg? You could probably do a number of things including adding considerable additional range, increase rapid and sustained fire rates, accuracy etc but clearly at the cost of mobility. The M777A2 is around 40% lighter than the M198 it replaced. Clearly a lot could have been done had the requirements called for the best possible gun within the M198s margins but given the expeditionary nature of the customer demand the focus was on reducing as much weight as possible to allow for this flexibility, and given the way and the places it has been, used it has paid off.

https://www.army.mil/article/182638/pic ... e_howitzer
Austin wrote:Show me one gun which did not including our own , Its like saying an aircraft should not crash at all during its life time ...heck we had a Jag exploding in mid air because of a fulty bomb that triggered in mid air and lost the aircraft.
This is why I had earlier emphasized the amount of usage, whether in trials, operationally or training this particular weapons system has been put through over the last decade plus. And not just in home environments but operationally 100% of the time in expeditionary environments in Afghanistan, Iraq and Syria. It is important to remember that while the aim is to have a very high system, and component reliability threshold there would still be failures and these will NEVER be completely eliminated. There is a good reason why the field manuals go into details on how to deal with such instances and why MTBF is constantly measured during testing and over the lifetime of the system. Same applies to the ammo. This is a combination (M777 and OFB ammo) that needs to successfully work to make these guns a success in the Indian Army so I'm sure the RCA will focus on the cause and recommend remedial measures for either the gun, round, or the TTPs so that this problem does not occur in the future.
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Re: Artillery Discussion Thread

Post by Singha »

>> Look at the way they pour powder into the brass. It's very uneven. This is likely how OFB does it's powder allocation.

I doubt it. making of bombs and shells at huge automated plants is a lot different from dara adam khel, they could not meet supply requirements in that mode nor meet any safety norms with tons of explosives lying around.
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Re: Artillery Discussion Thread

Post by Singha »

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Re: Artillery Discussion Thread

Post by Kakarat »

According to OFB website there are 3 types of 155mm HE shells under production
155 mm Shell HE 107
155 mm SHELL HE M/77B
SHELL 155 mm HE

We don't know which one is being used in these tests (both Dhanush & M777)

If M107 is the most produced and used then its time DRDO/ARDE start developing M107 replacement with private sector
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Re: Artillery Discussion Thread

Post by milindc »

Singha wrote:>> Look at the way they pour powder into the brass. It's very uneven. This is likely how OFB does it's powder allocation.

I doubt it. making of bombs and shells at huge automated plants is a lot different from dara adam khel, they could not meet supply requirements in that mode nor meet any safety norms with tons of explosives lying around.
Recent Chaiwalla discussion was that artillery shells by OFB is not different from dara adam khel. The artillery men actually shake the shell to see if there are any gaps in the power. :x
whole Chaiwalla gang was very mad at OFB quality.
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Re: Artillery Discussion Thread

Post by manjgu »

how many barrels burst during kargil when we fired huge numbers? how many shells were OFB vs imported in kargil? is the M777 is question a write off or is the barrel changed? they should i guess emboss the name of shift manager on the shells for RCA analysis !! poori accountability !
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Re: Artillery Discussion Thread

Post by negi »

I am amazed at how moment foreign weapon system gets involved people want to come up with all kinds of excuses ; I have seen how sales cycle happens for even a piddly SW product you go in completely prepared gold plated hardware , RAID 0 storage , low latency network cards etc etc and then you do your demos and trails . The M777 being field tested came from BAE factory do you think a western company picks a gun from a batch at random for field trials ? The sales team might have asked for the gun to be 'hand picked' and sent here , the only thing consistent here is OFB's shells :)
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Re: Artillery Discussion Thread

Post by Singha »

milindc wrote:]
Recent Chaiwalla discussion was that artillery shells by OFB is not different from dara adam khel. The artillery men actually shake the shell to see if there are any gaps in the power. :x
whole Chaiwalla gang was very mad at OFB quality.
all of this can surely be automated with better production machinery. maybe the labour unions want to keep it as a 100K strong cottage industry?

WAH ofb of the pakis looks quite streamlined

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Re: Artillery Discussion Thread

Post by geeth »

What if the M777 brought for trials is a used one and the barrel nearing the end of its life? In such case the clearances could be at the edge of its limits..and shell can misbehave.
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Re: Artillery Discussion Thread

Post by deejay »

^^^ I thought these guns are part of the 02 delivered to India which were to be used for trials after induction.
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Re: Artillery Discussion Thread

Post by brar_w »

geeth wrote:What if the M777 brought for trials is a used one and the barrel nearing the end of its life? In such case the clearances could be at the edge of its limits..and shell can misbehave.
The guns that were brought to India for testing years earlier (see my earlier post and link) likely came from US stock. These ones from what I have read, are fresh off the production line.
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Re: Artillery Discussion Thread

Post by milindc »

My discussion with chaiwala, and one of the topics was Artillery shells, was before the M777 incident. I came back thinking these OFBs should be disbanded.
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Re: Artillery Discussion Thread

Post by sudeepj »

milindc wrote:
Singha wrote:>> Look at the way they pour powder into the brass. It's very uneven. This is likely how OFB does it's powder allocation.

I doubt it. making of bombs and shells at huge automated plants is a lot different from dara adam khel, they could not meet supply requirements in that mode nor meet any safety norms with tons of explosives lying around.
Recent Chaiwalla discussion was that artillery shells by OFB is not different from dara adam khel. The artillery men actually shake the shell to see if there are any gaps in the power. :x
whole Chaiwalla gang was very mad at OFB quality.
Arty shells dont have 'powder' inside, the projectile is filled with plastic explosive with a wax like consistency. Even if you shake it, you wont hear anything! Its really insensitive too.. Were the high explosive inside the shell to explode in the barrel, there would not be much left of the gun or the crew! There is cordite or propellant inside single piece shells.. That could rattle a bit, but that isn't of any concern. Bofors and the M777 use a bi modular charge system for the propellant. The projectile and the propellant are two different pieces. Chaiwallas often tell tall tales, which often get even more unintelligible with retelling.

The OFB shell wobbling inside barrels, particularly in large caliber guns is an issue that could be caused by many things, including improper storage, bad design, improper methodology in use or plain manufacturing flaws. It could even be all of the above! Unless a proper analysis is done scientifically, pouring scorn on one thing or the other only shows the biases of the individual and has no relation to reality. For instance, this ndtv presstitute came up with a headline screaming 'faulty OFB shells cause shiny new imported howitzer to break..'. I wonder how this chap knows for sure even before the experts do? And I wonder what he is getting in return for putting his objectivity on ice and pushing for one thing over the other.
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Re: Artillery Discussion Thread

Post by ramana »

nvishal, Do you know for a fact that is how OFB makes shells like that video? If not please post elsewhere. It does not bring value to the discussion.
Singha. Again stop posting bokwas videos because you find them. What has it to do with the OFB shell exploding in the M777 gun?

Philip, You need to read my posts on how wobble happens.

Shell exploding in barrel is a rare thing but does happen.
The odd thing in India is so many happening during trials and exercise whether the gun is Bofors (40 times), upgraded 130mm barrels, Dhanush (1time), and now M777 (1 time).
When there is clearance due to excess gun barrel wear and under-dimensioned shell, when the shell is rammed with debris and gun is at high angle, when the gun bore is not evacuated, when fuze Safe and Arm is activated all these lead to shell bursts.

milindc, Can you confirm form the chaiwala that they saw the OFB shell making factory for the 155mm shells made same as that silly video?

I bet they cant. Its just prejudice.

OFB makes 155mm shells per M 756 spec in Ambajhari. It has a modern forging, heat treatment CNC machines to make the shells. The filling is done in a different factory.

http://www.ofb.gov.in/units/index.php?u ... es&lang=en

if OFB shells were katara, Indian Artillery would be self defeated in training exercises.

I think people should not misuse their stature to pass bogus comments.
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Re: Artillery Discussion Thread

Post by milindc »

I chatted with folks who are from the artillery brigade. Folks who take time off in Bhagyanagaram every year. FYI, I'm not expert. Just relaying my chaiwalla conversation.
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Re: Artillery Discussion Thread

Post by Singha »

Ndtv

Written by Vishnu Som | Updated: Sep 13, 2017 18:48

But today, in a statement to NDTV, the state-owned manufacturer which supplies at least 90 per cent of artillery shells in use with the Army, seemed to suggest that the failure was not unusual. "The number of rounds successfully fired during user trial with ERFB BT ammunition from [the] M-777 howitzer gun were more than 1,100 and the round in which malfunction occurred was [the] 1164th round," said Dr U Mukherjee, a spokesperson for the manufacturer.


When asked if this failure rate was acceptable, Mr Mukherjee said "Ideally, this is not acceptable."

Senior officers of the army told NDTV that the manufacturer's explanation was unacceptable and that they expect consistency in the quality of ammunition supplied to them. Experts from the Ordnance Board have visited the site of the trials and interacted with executives from BAE Systems, the manufacturer of the M-777 to determine what went wrong.

The OFB manufacturers shell hardware at the Ordnance Factory Ambajhari, Nagpur. Explosives are filled at its facilities at Chandrapur in Maharashtra and Bolangir in Odisha.
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Re: Artillery Discussion Thread

Post by Singha »

I check both the chandrapur and bolangir plants on google earth.
Both have extensive bunkers to store explosives and ready shells
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Re: Artillery Discussion Thread

Post by sudeepj »

Singha wrote:I check both the chandrapur and bolangir plants on google earth.
Both have extensive bunkers to store explosives and ready shells
Whoever is going to check this issue will need to check the storage dumps where the fired shell was stored through its life, not just the plants which likely only have temporary storage till the shells are shipped out to different storage dumps. It could even be an issue with Indian cordite burning hotter or possibly having some issues with the composition including some corrosive elements that causes barrels to wear faster.

The only thing that can be conclusively said is, shells are causing some issues in many different guns that we know of, so its likely not an issue in the guns. Exactly where the issue is, we can only say after a proper, scientific inquiry.
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Re: Artillery Discussion Thread

Post by Gyan »

negi wrote:I am amazed at how moment foreign weapon system gets involved people want to come up with all kinds of excuses ; I have seen how sales cycle happens for even a piddly SW product you go in completely prepared gold plated hardware , RAID 0 storage , low latency network cards etc etc and then you do your demos and trails . The M777 being field tested came from BAE factory do you think a western company picks a gun from a batch at random for field trials ? The sales team might have asked for the gun to be 'hand picked' and sent here , the only thing consistent here is OFB's shells :)
Shells are also carefully selected and old batches are not used for Trials.
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Re: Artillery Discussion Thread

Post by ramana »

Shells are also carefully selected and old batches are not used for Trials.
We know for a fact that shelf life for M 107 shell is 10 years and 20 years on life extension.

The shell that burst in Dhanush prototype was 12 years old.
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Re: Artillery Discussion Thread

Post by vasu raya »

sudeepj wrote: It could even be an issue with Indian cordite burning hotter or possibly having some issues with the composition including some corrosive elements that causes barrels to wear faster.

The only thing that can be conclusively said is, shells are causing some issues in many different guns that we know of, so its likely not an issue in the guns. Exactly where the issue is, we can only say after a proper, scientific inquiry.
Can they take X-ray pictures of the shell just after it is loaded into the gun, enabling to quantify the chemicals and their shape and feed these real world measurements to ballistics simulation software that can give the probability of successful fire?

Pooling data from hundreds of successful firings or otherwise from the field, one is increasing the confidence in the probability numbers given, should be possible as we have entered the big data era
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Re: Artillery Discussion Thread

Post by ramana »

Some data for RCA:
Singha wrote:Ndtv

Written by Vishnu Som | Updated: Sep 13, 2017 18:48

But today, in a statement to NDTV, the state-owned manufacturer {Why cant he say OFB?}which supplies at least 90 per cent of artillery shells in use with the Army, seemed to suggest that the failure was not unusual. "The number of rounds successfully fired during user trial with ERFB BT ammunition from [the] M-777 howitzer gun were more than 1,100 and the round in which malfunction occurred was [the] 1164th round," said Dr U Mukherjee, a spokesperson for the manufacturer.


When asked if this failure rate was acceptable, Dr Mukherjee said "Ideally, this is not acceptable."

Senior officers of the army told NDTV that the manufacturer's explanation was unacceptable and that they expect consistency in the quality of ammunition supplied to them. Experts from the Ordnance Board have visited the site of the trials and interacted with executives from BAE Systems, the manufacturer of the M-777 to determine what went wrong.

The OFB manufacturers shell hardware at the Ordnance Factory Ambajhari, Nagpur. Explosives are filled at its facilities at Chandrapur in Maharashtra and Bolangir in Odisha.

Facts from this news report:

1) Shell fired is the ERFB BT shell. OFB Link to ERFB BT

This means it is maximum range and hence maximum charge 8 or 9

2)1100 shells were fired successfully. Were all these ERFB shells or a mixture of M107 and ERFB shells? The 1164th shell had the accident.
Now what was the M777 barrel life for firing 155mm shells and the ERFB type shells?

Members can ask why am I asking this question?


In Vietnam, the US troops were firing the 175mm gun aka Long Tom against Viet Cong troops. They had instances of barrel burst.

The barrels had life of ~1200 firings but were failing at ~450. Many of the guns were stopped and investigation launched as to what was happening. Appears guns were being fired at max charge to hit the attackers at farthest distance possible. What this did was to create high stresses in the barrel and that caused fatigue micro cracks. Further firing would burst the barrel. Others had excessive internal wear that caused balloting our favorite phenomena!!!!

So if any one can find out what is the M777 barrel life is for conventional and ERFB type shells would appreciate.
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Re: Artillery Discussion Thread

Post by ramana »

sudeepj, The OFB webpage I linked above says the shells have to be stored at 21 +/- 2 degree C.


However I don't think the shell explosive deteriorated and blew up.

It got shocked in the barrel.

Wonder why the Fuze is not being questioned.

OFB webpage says PD M 572 or the ECIL M85 P13A3. So which was the fuze used here.

We know PD M572 has issues in long barrels per the Janes transcript linked so many pages ago by tsarkar.
Essentially the safety is defeated inside long barrels at high charge due to the spin rate.
Rifling rate assumed to be 1: 20 calibers the standard.
And if it strikes the side i.e. wobble off it goes from the graze function in the fuze.


What was the fuze used in series of Bofors, 130 mm upgraded barrels, Dhanush, and this M 777 accidents?
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Re: Artillery Discussion Thread

Post by ramana »

I found via Google chacha Wear and Erosion of Large Caliber Gun Barrels. Its report from US lab on the phenomena.

I think this thread participants could use this gnan.

Also please read this about how the M777 was developed and qualified.


Army Guide-M777

Am quoting only relevant portions. Interseted can read the webpage.

Initial proof of concept
The complete upper part of the weapon was test fired at Eskmeals in June 1989 with a total of 50 rounds being fired at all elevations, 12 of which were zone 8S (top charge).
and
Following its unveiling at the 1989 Association of the United States Army Exhibition in Washington DC, one of the two prototypes went to the US for early evaluation. ...
Under the five-year Engineering and Manufacturing Development (EMD) contract a total of nine systems were built at the BAE Systems Land Systems facility at Barrow-in-Furness. These have underwent an extensive series of tests in the US during which more than 10,000 rounds of ammunition have been fired.
So qualification trials the gun was fired assuming equal usage 10000/9 = 1100 rounds of fire!!!!

And Pokhran trials had gun that was firing its 1164 round.

Just some perspective.

What is the BAE guarantee for M777 barrel life?
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Re: Artillery Discussion Thread

Post by brar_w »

Generally in developmental testing, not all are performing the same function. There would have been examples used for durability, weather, mobility, logistical footprint testing etc etc. Also note that these were developmental test articles. US DOD testers did not agree with the program office when it came to using guns produced in England for Operational Test and evaluation as they wanted something produced under the production arrangement that would represent operational articles (70% work subcontracted to US firms). So operational testing of full production representative variants was over and above developmental testing efforts that took place earlier This delayed the program by 2 years as production transitioned into LRIP in order to provide production representative guns for the OT&E to take place later .

Image
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ramana
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Re: Artillery Discussion Thread

Post by ramana »

So can you figure out what was the barrel life for M777 of the US production lots?
There are manuals of the M777 gun on the web which I couldn't read.
Specifically for the M 777 gun when is a barrel due for change? After how many rounds?
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Re: Artillery Discussion Thread

Post by ramana »

Ok. From brar_w chart posted above the Cannon specification fatigue life is 2650 EFC which is means much more actual number of shells fired. And the fatigue life exceeds the wear life. The demonstrated fatigue life would be much, much more.

What this tells us is the gun barrel can withstand 2650 EFC which is less than actual shells firing.
So Pokhran test firing of 1100 shells did not cause barrel fatigue.

However the wear life is less than the fatigue life. We need to look this factor.

BTW from tejasmrca site the M 777 is great gun.

http://tejasmrca.weebly.com/land-system ... t-howitzer

Its light, its 39 calibers long like the Bofors, and is very accurate at intermediate ranges with CEP of 20m
At intermediate ranges the M-777 unguided shells can be expected to land within 20m of their target. However, the HE shells having a kill radius of 35m makes up for the large CEP. This however has not limited the M-777 to demonstrate accurate and effective fire against targets in Afghanistan at ranges of 22 miles.
Looking at the barrel being 39 calibers and the maker is BAE, maybe this is the redesigned Bofors?

IA should look at the old 40 shell failures of the Bofors to see if there is pattern.
Locked