Carl N. Brown
Member
Reports of damaged Garand operating rods demonstrate that there are enough exceptions that Garand owners need to be very careful about ammo selection.
Warning from CMP
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Reports of damaged Garand operating rods demonstrate that there are enough exceptions that Garand owners need to be very careful about ammo selection.
Garandimal
member
I just happen to have a 1st Edition copy sitting on my desk. (Yes, that makes me special)
Why, Yes.... Yes, it does.GR
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Jeremy2171
Member
Jeremy2171
Member
Yes..thats why the army made lots of extra oprods and had jigs to put them back into spec again... Oh wait...that was WITH GOVT. M2 Ball and AP and other ISSUED ammo not commercial ammo.
So we have oprods getting bent due to M2 ball...
Maybe its not the ammo...but poor lubrication and improper disassembly?
Oprods get tweaked in the handle area...this comes from the interaction with the bolt lug and the unlocking action.
Carl N. Brown
Member
I have a reprint of Hatcher's Manual in a leatherbound reprint by Kingsport Press.
It is second only to my paperback copy of the Necronomicon as unquestionable authority.
It is second only to my paperback copy of the Necronomicon as unquestionable authority.
This is what the CMP sent me
Having been down there a number of times, if they are putting that out, then it is because they are seeing things at the range, like kaboom's, and sales are hearing things, that you are not. I do know from a fellow shooter, who was at a Garand Match, and he said the head of the Garand Collector's society had an out of battery that ruined his rifle.
The original specs for the M1903 were a not to exceed 50,000 cup, and at the time, CUP was understood to be PSIA. Understand that? Their measuring devices, which were copper crusher pellets, were calibrated against a static load of 50,000 pounds. Designers created enough material, and used appropriate safety factors, for a cartridge that was not to exceed 50,000 psia. The structure of the rifle was designed for a maximum of 50,000 psia.
The dynamic response of copper was such, the actual cartridge pressure was higher, but powder technology advanced. The Army saw little to no need to change the velocity of their cartridges, I know the "more means more" crowd will be horrified by this, but changing velocity meant changing rear sights, books, etc. And what would it really gain?
By the time you get to WW2, powder technology had advanced. Pressures were less for the same velocity. It turns out pressures with IMR 4895 were in the lower 40,000 cup range with either the 174 FMJBT or the 150 FMJ. And, more importantly, the gas system of the Garand was tailored for the cartridges of the time. You hop up the gas pressure in the barrel of your Garand, just because you want faster ammunition, and that may knock off the heel of your rifle.
This unhappy poster used CMP Greek ammunition in his Garand.
Some of that CMP Greek ammunition is over pressure due to age. And when that bolt rebounds off the heel of an old receiver, well given enough previous impacts, sometimes these things crack. I talked to a man who was on a rebuild line, they scrapped a lot of Garand receivers that developed heel cracks.
I have seen malfunctions in Garands due to commercial ammunition. Cartridge clips jumping out and jamming. Keep pressures low and don't use powders slower than IMR 4064 in a Garand. I recommend IMR 4895/AA2495/H4895, 47.5 grains with a 150 grain bullet. Too bad short cut IMR 3031 is only a recent phenomenon, IMR 3031 is a little faster than IMR 4895, and at Garand velocities, ought to be even easier on the gas system. But since IMR 4895 was the WW2 powder, and the National Match ammunition powder, you can't go wrong with it. H4895 and AA2495 are so close to IMR 4895, just buy by price.
I do know, from a shooter who worked at an Army Ammunition plant, by the time the Army was using WC852 powder, cartridges were loaded to a velocity, because powder technology had advanced enough, they did not have to worry about exceeding the pressure spec at that velocity.
Something about those very old 1903's, double heat treated receivers particularly. The Army bought a huge quantity of steel during WW1, and kept using it till it ran out. Which was in 1927. It takes work, but you can find double heat treat kaboom's. Now there is a cult of the double heat treat, all based on Hatcher's writings, but you gotta remember, the Army believes its own propaganda. The steel was plain carbon steel, and wartime production is always made according to the "git er out the door" philosophy. "We don't need an "A", an "F" is a failure, but a "D" is good enough!" And, the steel processing technology of the period produced crappy steel. And then, factory instrumentation was pretty primitive. Those old receivers are made out of inferior materials, under primitive process controls, and they are old. I think the nickle steel receivers are the best, but they are still old receivers, and no doubt, the CMP has seen enough kabooms to become worried about the things.
Having been down there a number of times, if they are putting that out, then it is because they are seeing things at the range, like kaboom's, and sales are hearing things, that you are not. I do know from a fellow shooter, who was at a Garand Match, and he said the head of the Garand Collector's society had an out of battery that ruined his rifle.
The original specs for the M1903 were a not to exceed 50,000 cup, and at the time, CUP was understood to be PSIA. Understand that? Their measuring devices, which were copper crusher pellets, were calibrated against a static load of 50,000 pounds. Designers created enough material, and used appropriate safety factors, for a cartridge that was not to exceed 50,000 psia. The structure of the rifle was designed for a maximum of 50,000 psia.
The dynamic response of copper was such, the actual cartridge pressure was higher, but powder technology advanced. The Army saw little to no need to change the velocity of their cartridges, I know the "more means more" crowd will be horrified by this, but changing velocity meant changing rear sights, books, etc. And what would it really gain?
By the time you get to WW2, powder technology had advanced. Pressures were less for the same velocity. It turns out pressures with IMR 4895 were in the lower 40,000 cup range with either the 174 FMJBT or the 150 FMJ. And, more importantly, the gas system of the Garand was tailored for the cartridges of the time. You hop up the gas pressure in the barrel of your Garand, just because you want faster ammunition, and that may knock off the heel of your rifle.
This unhappy poster used CMP Greek ammunition in his Garand.
Some of that CMP Greek ammunition is over pressure due to age. And when that bolt rebounds off the heel of an old receiver, well given enough previous impacts, sometimes these things crack. I talked to a man who was on a rebuild line, they scrapped a lot of Garand receivers that developed heel cracks.
I have seen malfunctions in Garands due to commercial ammunition. Cartridge clips jumping out and jamming. Keep pressures low and don't use powders slower than IMR 4064 in a Garand. I recommend IMR 4895/AA2495/H4895, 47.5 grains with a 150 grain bullet. Too bad short cut IMR 3031 is only a recent phenomenon, IMR 3031 is a little faster than IMR 4895, and at Garand velocities, ought to be even easier on the gas system. But since IMR 4895 was the WW2 powder, and the National Match ammunition powder, you can't go wrong with it. H4895 and AA2495 are so close to IMR 4895, just buy by price.
I do know, from a shooter who worked at an Army Ammunition plant, by the time the Army was using WC852 powder, cartridges were loaded to a velocity, because powder technology had advanced enough, they did not have to worry about exceeding the pressure spec at that velocity.
Something about those very old 1903's, double heat treated receivers particularly. The Army bought a huge quantity of steel during WW1, and kept using it till it ran out. Which was in 1927. It takes work, but you can find double heat treat kaboom's. Now there is a cult of the double heat treat, all based on Hatcher's writings, but you gotta remember, the Army believes its own propaganda. The steel was plain carbon steel, and wartime production is always made according to the "git er out the door" philosophy. "We don't need an "A", an "F" is a failure, but a "D" is good enough!" And, the steel processing technology of the period produced crappy steel. And then, factory instrumentation was pretty primitive. Those old receivers are made out of inferior materials, under primitive process controls, and they are old. I think the nickle steel receivers are the best, but they are still old receivers, and no doubt, the CMP has seen enough kabooms to become worried about the things.
Jeremy2171
Member
Your receiver heel was cracked due to "high" oprod velocity....THAT usually comes from worn springs.
A short 19" spring compared to a new Orion7 spring made the bolt/oprod move 10-12% FASTER than a inspec spring. That is causing some hammering at the heel.
Since CMP sends out rifles with worn and broken springs and many new garand owners don't know much and "assume" the rifle is ready go out blasting. These results aren't surprising.
Then again...the govt had cracked receiver heels a well....same thing..worn springs.
A short 19" spring compared to a new Orion7 spring made the bolt/oprod move 10-12% FASTER than a inspec spring. That is causing some hammering at the heel.
Since CMP sends out rifles with worn and broken springs and many new garand owners don't know much and "assume" the rifle is ready go out blasting. These results aren't surprising.
Then again...the govt had cracked receiver heels a well....same thing..worn springs.
Swampman
Old Fart
Wow!
TWO YouTube videos that you probably made yourself.
We obviously have different definitions of what constitutes a "reputable source"...
Attachments
Jeremy2171
Member
Yeah I guess actual chrony readings don't count...lol I guess you don't like data?
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Garandimal
member
The Church of the Speeding Op-rod...?
... does not constitute proof of anything - beyond your religious devotion to a hoax.
You are being held hostage against Physics.
A Must Read for the Civilian M1 Rifle Owner:
The M1 Garand and Commercial Ammunition
The M1 Garand Gas Cycle
To interpret the data provided, we will need to define the gas cycle. The gas cycle on the M1 Garand can be broken up into several distinct stages. Each stage affects how the pressure in the gas cylinder is changing. The Gas cylinder and operating rod assembly on the M1 are lossy. That is to say, gas is always flowing past the gas piston when the pressure in the gas cylinder is greater than the pressure outside of the gas cylinder. The following stages will deal with gas flowing into the gas cylinder. A graph of a typical gas cycle when using M2 ball (HXP) is shown in Figure 2.
Stage 0: The first stage consists of the bullet traveling up the barrel, compressing the air in front of it. The bullet moves up the barrel faster than the gas can escape from it. This causes the pressure to rises in the barrel. This stage ends when the bullet has moved up the barrel and is blocking the gas port. The compressive force of the bullet traveling up the barrel combined with gas blow-by will pressurize the gas cylinder to approximately 10psi. This initial pressure transient is what we use to start the data acquisition process.
Stage 1: This stage is defined as the bullet having moved forward of the gas port, but is still in the barrel. This stage is responsible for the highest rate of change of pressure over time (dp/dt). However, it is also the shortest of the stages, lasting approximately 46 microseconds.
Stage 2: The bulk of the gas transfer will occur during this stage. The bullet has left the barrel and the barrel is now rapidly depressurizing. However, the pressure in the barrel is still greater than that in the gas cylinder; therefore, gas continues to flow from the barrel into the gas cylinder.
Stage 3: Pressure equalization has occurred in this stage. It marks the point of peak pressure in the gas cylinder. From this point forward, gas will be flowing from the gas cylinder back into the barrel. Gas is also flowing past the piston and exiting the gas cylinder as previously mentioned.
Stage 4: The gas cylinder is depressurizing. This stage normally lasts approximately three milliseconds.
Stage 5: The M1 Gas cycle is now complete. The gas cylinder has depressurized. The operating rod has reached its peak momentum. At this point the operating rod has moved rearward approximately 3/8 of an inch. The operating rod will coast rearward using the kinetic energy it gained to perform functions such as: unlocking the bolt, extracting the empty cartridge case, cocking the hammer, and compressing the operating rod spring.
... if you plan to shoot modern, high power hunting ammo out of it.
GR
Jeremy2171
Member
You continually cutting and pasting doesn't prove your point.The Church of the Speeding Op-rod...?
... does not constitute proof of anything - beyond your religious devotion to a hoax.
You are being held hostage against Physics.
A Must Read for the Civilian M1 Rifle Owner:
The M1 Garand and Commercial Ammunition
The M1 Garand Gas Cycle
To interpret the data provided, we will need to define the gas cycle. The gas cycle on the M1 Garand can be broken up into several distinct stages. Each stage affects how the pressure in the gas cylinder is changing. The Gas cylinder and operating rod assembly on the M1 are lossy. That is to say, gas is always flowing past the gas piston when the pressure in the gas cylinder is greater than the pressure outside of the gas cylinder. The following stages will deal with gas flowing into the gas cylinder. A graph of a typical gas cycle when using M2 ball (HXP) is shown in Figure 2.
Stage 0: The first stage consists of the bullet traveling up the barrel, compressing the air in front of it. The bullet moves up the barrel faster than the gas can escape from it. This causes the pressure to rises in the barrel. This stage ends when the bullet has moved up the barrel and is blocking the gas port. The compressive force of the bullet traveling up the barrel combined with gas blow-by will pressurize the gas cylinder to approximately 10psi. This initial pressure transient is what we use to start the data acquisition process.
Stage 1: This stage is defined as the bullet having moved forward of the gas port, but is still in the barrel. This stage is responsible for the highest rate of change of pressure over time (dp/dt). However, it is also the shortest of the stages, lasting approximately 46 microseconds.
Stage 2: The bulk of the gas transfer will occur during this stage. The bullet has left the barrel and the barrel is now rapidly depressurizing. However, the pressure in the barrel is still greater than that in the gas cylinder; therefore, gas continues to flow from the barrel into the gas cylinder.
Stage 3: Pressure equalization has occurred in this stage. It marks the point of peak pressure in the gas cylinder. From this point forward, gas will be flowing from the gas cylinder back into the barrel. Gas is also flowing past the piston and exiting the gas cylinder as previously mentioned.
Stage 4: The gas cylinder is depressurizing. This stage normally lasts approximately three milliseconds.
Stage 5: The M1 Gas cycle is now complete. The gas cylinder has depressurized. The operating rod has reached its peak momentum. At this point the operating rod has moved rearward approximately 3/8 of an inch. The operating rod will coast rearward using the kinetic energy it gained to perform functions such as: unlocking the bolt, extracting the empty cartridge case, cocking the hammer, and compressing the operating rod spring.
...and one of these:
... if you plan to shoot modern, high power hunting ammo out of it.
GR
Since as usual you don't understand where and when the damage occurs...and it doesn't happen when the gas hits oprod piston....you know the thing supported by a spring..that doesn't move until AFTER the bullet has left the bore..damage occurs in the latter part of stage 5 when unlocking the bolt happens.
So please do more research before trying to pass that one off.
Stop ignoring physics...
Nature Boy
Member
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- Apr 21, 2015
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I give @Jeremy2171 credit. He did his own testing, showed his data and used it to support his conclusions.
Risky buisness
Member
In looking at SAMMI specs for. 458, 53,000 lb was somehow mentioned there, interesting that 50,000 lbs is fairly consistent in reporting what max psi the Garand operates at. That would generally alude to the fact that a rifle using 50k psi is not rated to run ammunition pushing 53k.
" already been done, perfectly safe " If it's your rifle your running 458 in, I'm glad your still around to write the praises of that conversion, do tell....what bullet weights do you find " perfectly safe " to fire?
Jeremy2171
Member
Are you looking at 50,000 psi OR 50,000 CUP.... there IS a difference.
Risky buisness
Member
Obviously their is a difference. Copper units for the 458 @53000. CIP rated @ 61000. Garand still listed as a 50,000 CUP rated rifle design
So, please have fun with your rifle.
So, please have fun with your rifle.
Jeremy2171
Member
And don't forget those 308/762 garands.
308 is 52k CUP. Yet the military converted them to that. So 50k cup isn't the max.
Risky buisness
Member
Yes, the military did convert M1s to 7.62x51, most probably as a stopgap untill the M14 came on board. They also didnt chrome line M16 bores, all of this is subjective, because you feel its appropriate to convert a rifle designed for a particular cartridge to another it is not designed for is all you. Because someone hasn't been harmed or has and not reported still doesn't make it correct to do this in my opinion. If you feel it's safe to do this, go ahead.
Jeremy2171
Member
It's not subjective...the Navy converted them because they didn't want to buy M14s and had plenty of M1s. Italy converted them to 308/7/62 and then made the BM59 select fire variant.
308/762 garand have been around since the 60's. 52k CUP isn't an issue
Lets not forget that SA Inc made garands in .270 win....which is.... wait for it.... 54k CUP.
So again.... lots of worrying over nothing...
Risky buisness
Member
Ok then.... lots of worry over nothing. I can understand the points your making with folks exceeding designed specifications, it is however subjective, as a finite observation of the conversion would have disallowed it whereas the we can get by doing it crowd ignored it. I still have no plans to convert any of my Garands to another cartridge and utilize Schuster gas relief plugs, load conservatively and have studied the pressure curves for the operating system to make sure that I'm not damaging them or me in the process.
Thanks for the discussion
Thanks for the discussion
Jeremy2171
Member
Actually it wouldn't have disallowed it.. the receiver is way stronger than the 50k CUP as evidenced by actual destructive testing by JCG himself.
I don't use any sort of gas relief items as they aren't really needed unless you pan on handloading some crazy long range ammo.
I don't use any sort of gas relief items as they aren't really needed unless you pan on handloading some crazy long range ammo.
Risky buisness
Member
Jeremy, believe me when I say this, I'm very positive that I can get away with higher pressure loadings, different cartridge options and no gas system vent plugs, you have layed out lots of reasons why you do what you and some are quite convincing, however, I dont think that I'm going to go that route, I'm kinda that guy, that rather than hot load a particular cartridge for higher performance I'm going to pick up one that has that performance already. But like I said, you do have some convincing arguments.
MachIVshooter
Member
CMP is operating under the (very reasonable) assumption that most people who buy these rifles are going to take them out and shoot them as received, a cursory prior inspection and cleaning at best. If owners want to inspect their weapons in detail and replace/upgrade parts to use hotter ammunition at their own risk, that's their business. The warning exists for good reason, though.
The receiver doesn't contain pressure under firing. That's the chamber. The receiver deals with vectored forces and impacts, as does the bolt. That's where the issue arises. Just because a chamber can take well more than a given pressure doesn't mean the bolt lugs and receiver recesses for those lugs can handle the bolt thrust, especially when you increase case head diameter and turn that small chamber pressure increase into a very large bolt thrust increase.
If you want to chamber your personal weapons in belted magnum cartridges, go for it. But it is recklessly irresponsible to tell others that nearly doubling the force of what parts are designed for is safe. The guns are old, they are made with early 20th century metallurgy and in the hasty ways of wartime production. Late M1s with 8620 receivers & bolts are gonna be tougher, but you didn't bother to qualify your statements with such important details, and they still aren't designed to handle high pressure belted magnum rounds.
Just because something has worked doesn't mean it's a good idea. I moved my 11,000 lb CNC lathe with my 8,000 Lb rated CAT V80 forklift. I was taking a risk, and I knew it. It worked out, but I wouldn't tell anybody that it's perfectly safe to do so.
You speak like someone who has pushed the limits and been lucky to date. You'll find a new reverence for the power you're dealing with when one blows up in your face, assuming you survive. It's scary having a .30-06 you're shooting let go. I was very lucky to only get peppered and have my ears rung good.
After the bleeding stopped:
Fortunately I had eye pro. I was digging powder granules and other debris out of my face for weeks.
When it comes to firearms, the risks are well more than damaging expensive material things; you cannot buy new eyeballs or replace a life lost. Act accordingly.
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The CMP is seeing stuff, at a frequency, we are not. Kind of like the coroner, everyone on his slab can only die once. But coroners sees enough stiffs, they can see patterns the dearly departed won't.
Let us understand that the Garand was built against a number of requirements. One was, it and the M14 had to shoot 6000 rounds. That was the endurance testing. If the rifle fired 6000 rounds without breaking, it was considered good enough for combat. I am going to claim the lifetime of a rifle in combat was actually longer than the user. During WW2, most of the Doggies, were blowed up, within a couple of months after arriving in theater. (I found that the average lifetime of a Russian Infantry Solider during the Battle of Stalingrad was 24 hours!) The attrition of new guys was terrible. I read a book by an Infantry Company Officer in France/German. It was 9 months from arrival till he got the bad one. And when he talked to the hospital staff, none of the medical staff had ever seen a front line solider who had been in combat nine months. Generally speaking, Dogfaces were broken, buried, or blown into pieces, well before nine months.
Now, once a Garand was "worn" out, so worn out that unit maintenance could not fix it, and the rifle was sent to Depot. It was perfectly acceptable that any, or all parts, could be tossed in the rebuild process.
Civilians want their thundersticks to last forever, so much so, that they tend to be in denial that the military had not built forever rifles.
Bolts crack by the way, and the receiver heel, I don't know what the fatigue lifetime is, but hit it enough, and it will crack. And hit it harder, by over accelerating the bolt, and it will break sooner.
I am curious about a couple of things. That sure looks like an over pressure cartridge. Was it factory, or reloads? And, what blew off into your face. I had an out of battery with Federal Match primers where the elevation knob was peeled off, stock blown in half, and powder particles all over my face. Thankfully, was wearing my glasses.
And, I have a couple of pictures, a guy with a mustache, who was hit in the eye with the blown off receiver heel from a M1 HRA. The story was it was an out of battery incident. But, the mustache looks so similar I wonder if you had more than one accident.
Good you were wearing your safety glasses. Getting blowed up does a couple of things: 1) you don't feel invincible or untouchable afterwards, and 2) you are thankful for safety glasses.
MachIVshooter
Member
It was a Winchester 1917 Enfield that had been reamed to something else .30 caliber and not marked. I didn't check. Should have, being a used gun, but had no reason to suspect it wasn't still a .30-06.
The debris was mostly powder granules that blew back through the receiver, some pieces of brass. The bolt held, but the bolt catch was blown out & spring damaged, extractor bowed. Good thing it was a 1917, others may not have held.
Other image you saw, no, not me. My M1 is still in one piece.
Jeremy2171
Member
You missed the gist of my conversation...JCG tested them to destruction and way over proof load levels. Around 120k CUP the brass flowed and wrecked things. They replaced the damaged parts reinspected it and sent it back out.
Another rifle cracked the left bolt lug above proof load levels.. the shot it another 5000 rounds of ball with no issues AND the cracked lug. Replaced and sent it out..
So because I said receiver...I meant the "action" as in all the parts together are far stronger than 50k CUP
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