My advice for reloading for Garands/M1as is to
1. Full length resize in a small base die
2. Trim cases
3. Clean primer pockets, ream to depth
4. Prime all cases by hand, verify that all primers are below the case head, and use the least sensitive primers you can find.
5. Use IMR4895/AA2495/H4895 powders.
6. Seat the bullets to magazine depth, no longer than 3.3” inches for the 30-06, no longer than 2.8 for the 308, shorter is fine.
For case life, I am lubricating my cartridges. Experienced shooters recommended to me that I only take a case four or five reloads, which is about 5 to 6 firings, and discard the cases. I would be shown their cases, I would take them home, section them, and find that their cases had severe case head stretch. I followed their advice until I met a Distinguished HM who was shooting lubricated cases in his M1a. He left the RCBS case lube on his cases, never tumbled or cleaned them, and he said he could take a set of brass all shooting season.
Cost is an important consideration to me. There are those to whom case life and case cost are irrelevant, but few people got to retire with footlockers of free military brass. I have noticed that new “bargain” 308 Win is priced $22.00 for twenty rounds, so brass has become even more expensive over the years. While I cannot speak for others, but for me, saving money is important: the cost of replacing cases after five firings is significant, especially if you are shooting to earn the Distinguished Rifleman’s Badge . Being able to take a set of brass 10 or even 20 times results in considerable cost savings over the alternative of tossing the brass after five firings.
Brass life in a bolt rifle can be orders of magnitude higher than what a gas gunner can expect. Bolt rifles are easy on brass, less scratches and dents, and the brass is not stretched on extraction because the bolt is opened after chamber pressure is zero. When bolt gunners get case head separations it is primarily due to setting the shoulder too far back on sizing. Cases are really meant to stretch once, on the average, 0.005”-0.006”. If cases stretch more than that depending on a number of variables, brass hardness being a primary factor, cases will break above the case head. Such as what this reloader experienced with 300 WSM rounds.
If a bolt gunner only pushes the shoulder back 0.003” his brass has the potential to last tens if not hundreds of reloading cycles.
M1’s, M1a’s, are much harder on brass than bolt rifles. Gas guns are very hard on brass and it is because they unlock while there is still pressure within the barrel. Col Chin calls this the residual blow back effect. This is deliberate and aids in the function of the mechanism. Residual blow back effect will get the case moving out of the chamber if case to chamber friction is low. Unlock must occur while pressures are below case sidewall rupture strength. This also has the effect of stretching the case. Hatcher explained, in Army Ordnance Magazine, March-April 1933, how cases stretch and why lubrication is essential in retarded blow back mechanisms:
Automatic Firearms, Mechanical Principles used in the various types, by J. S. Hatcher. Chief Smalls Arms Division Washington DC.
Retarded Blow-back Mechanism………………………..
There is one queer thing, however, that is common to almost all blow-back and retarded blow-back guns, and that is that there is a tendency to rupture the cartridges unless they are lubricated. This is because the moment the explosion occurs the thin front end of the cartridge case swells up from the internal pressure and tightly grips the walls of the chamber. Cartridge cases are made with a strong solid brass head a thick wall near the rear end, but the wall tapers in thickness until the front end is quiet thin so that it will expand under pressure of the explosion and seal the chamber against the escape of gas to the rear. When the gun is fired the thin front section expands as intended and tightly grips the walls of the chamber, while the thick rear portion does not expand enough to produce serious friction. The same pressure that operates to expand the walls of the case laterally, also pushes back with the force of fifty thousand pounds to the square inch on the head of the cartridge, and the whole cartridge being made of elastic brass stretches to the rear and , in effect, give the breech block a sharp blow with starts it backward. The front end of the cartridge being tightly held by the friction against the walls of the chamber, and the rear end being free to move back in this manner under the internal pressure, either one of two things will happen. In the first case, the breech block and the head of the cartridge may continue to move back, tearing the cartridge in two and leaving the front end tightly stuck in the chamber; or, if the breech block is sufficiently retarded so that it does not allow a very violent backward motion, the result may simply be that the breech block moves back a short distance and the jerk of the extractor on the cartridge case stops it, and the gun will not operate.
However this difficultly can be overcome entirely by lubricating the cartridges in some way. In the Schwarzlose machine gun there is a little pump installed in the mechanism which squirts a single drop of oil into the chamber each time the breech block goes back. In the Thompson Auto-rifle there are oil-soaked pads in the magazine which contains the cartridges. In the Pedersen semiautomatic rifle the lubrication is taken care of by coating the cartridges with a light film of wax.
Blish Principle….There is no doubt that this mechanism can be made to operate as described, provided the cartridge are lubricated, …. That this type of mechanism actually opens while there is still considerable pressure in the cartridge case is evident from the fact that the gun does not operate satisfactorily unless the cartridges are lubricated.
While neither the Garand or M1a is a retarded blowback action, cases are stretched in these mechanisms. Case life can be greatly extended by the practice of cartridge lubrication.
These images are of typical dry cases fired in a M1a. These are from a shooting bud's M1a and they are five times fired and they were fired as dry cases in a dry chamber. Scratches are from a bent paperclip inserted in the case mouth, I was trying to find the side with the deepest stretch ring.
These are cases fired in my M1a and fired as lubricated rounds. For the majority of firings these cases were sized in an RCBS small base die. I use RCBS water soluble case lube and I set up my 308 dies with a Wilson gage and a Barnett reamer cut gage. I size the cases to gage minimum or if the brass is to be fired in only one M1a, I push the shoulder back 0.003”. I either left the RCBS case lube on them and primed them that way, or I put on Johnson paste wax on the loaded cases with my fingers. I don’t like the feel of greasy cases and if I had time between matches I would wash the cases to remove the RCBS lube and then apply paste wax. If I did not have time I fired the cases just as they came out of the die, minus whatever lube that was lost in handling. I never had a primer dud.
I ran a number of experiments with various lubes; leaving thick coatings of grease is objectionable as grease particles are in the air after firing. I had 1000 rounds of CAVIM and I fired most of them in a FAL. FAL’s are very hard on brass and I experimented with stick wax. This is a tenuous grease used to lubricate saw teeth. I dropped lumps of stick wax in a bag with handfuls of CAVIM and shook vigorously. Both case and bullets were unevenly coated with globs of stick wax. When I fired this stuff it was as if a grease bomb went off: the mechanism and myself became coated in stick wax. My shooting glasses had to be frequently cleaned, my hands were greasy, my clothes were greasy, overall, it was messy. Later I spent hours wiping the cases to reduce the amount of stick wax.
The picture below are of sectioned cases, R stands for reloaded, R5 five times reloaded, etc, all of these cases the shoulder was set back about 0.003” and the cases fired in my M1a. I do not visually see any evidence of case wall thinning from those cases reloaded 5 times (6 times fired) , R18, or R22. As long as the case is not excessively stretched during firing or extraction, there is no reason for the sidewalls to thin. The FAL cases are from a Bud’s rifle. I think they were separating after 2 or 3 three firings, FAL’s are hard on brass.
At Camp Perry in cold weather I had bolt over rides with some of my Johnson paste waxed rounds. This ended when I polished the rounds. Pervious to that I shot the rounds with swirls and gobs of paste wax but evidentially that caused sluggish round rise in the magazine in cold weather. From then on I polished my rapid fire rounds and have never had a bolt close on an empty chamber even in rapid fires sequences in snow.
I have tried various lubes, paste wax takes the most time to apply but is the most satisfactory for handling. Paste wax dries hard, it is easy to wipe off dirt if you drop a round, and it is cheap. I am of the opinion that Johnson paste wax is similar to the coating that John Pedersen used for his 276 Pedersen ammunition.
http://www.google.com/patents/US1780566
Patented Nov. 4, 1930 PATENT OFFICE JOHN DOUGLAS PEDERSEN, OF SPRINGFIELD, MASSACHUSETTS 11,0 Drawing.
This invention relates to a process for coating cartridges and more particularly the affixing of a coating of hard wax to the metal case of a cartridge; and the object of the invention is to provide a method whereby cartridges may be coated with great uniformity with an extremely thin film, and also whereby a relatively large number of cartridges may be coated in a short time and at small cost.
In the preparation of cartridges having metal cases for storage and for use, it has been found desirable to apply to said metal case a relatively thin coating of some protective substance which will preserve said metal case for comparatively long periods of time against-deterioration, such as season cracking. In the present invention, the material for said coating has been so chosen as to perform the additional function of acting as a lubricant for the case of the cartridge, both for facilitating introduction into the chamber of the gun and the extraction thereof after firing. The most suitable wax which I have found for this purpose and which I at present prefer is ceresin, a refined product of ozokerite; but I wish it to be understood that other waxes having similar qualities may exist which might serve equally well. Some of the desirable features of ceresin are that it is hard and non-tacky at ordinary temperatures having a melting point somewhere between 140 and 176 Fahrenheit. It is smooth and glassy when hard and does not gather dirt or dust. However, when the ceresin on the cartridges is melted in the chamber of a gun, it becomes a lubricant.
Other lubricating waxes have been employed for coating cartridges, and the method most generally pursued for applying said coating to the cartridge case has been to prepare a heated bath of a solution of the wax in a suitable solvent, dip the cartridges therein so that a film of the solution will adhere thereto, and finally withdraw the cartridges to permit the solvent to evaporate from the coating film. This former process is comparatively slow and has been found lacking in several important respects.
My basic conclusion is that if the brass does not failure through case neck cracks, body splits, and you have not stretched them so they develop case head separations, you can load them until the primer pockets get too large , which is why I stopped reloading these cases.
I found that I needed to periodically ream the primer pockets: the pockets became shallow. Don’t know why unless the primer pocket collapses over time. As incidental contact with the primer can cause a slamfire or an out of battery slamfire, keeping the primer below the case head is a safety critical issue.
I can say I earned my Distinguished and won a regional gold with lubricated cases in the M1A, so my accuracy and function with lubricated cases was more than acceptable.
These targets are all with lubricated cases fired in 100 yard reduce course matches. The slow fire prone stage is 20 shots for record fired in a time limit of 20 minutes. All of these targets are 20 shot groups fired in competition. Accuracy for all was acceptable.
308 NM Garand 2013
200 yard prone 5 V target
30-06 NM Garand
2009
2011
2012
200 yards 5 V target
Rack Grade Garand, 200 yards Match, prone with sling. I left the RCBS case lube on the cases as I did not have the time to remove it and apply Johnson paste wax.
