What type of primer is everyone using in the Garand?
I have some very strong opinions on reloading for Garands. That rifle has a long free floating firing pin, and it does not take a long search before you find other people who have had slamfires in the thing. The worst type of slamfire is the out of battery slamfire. I had two. The last one knocked the back of the receiver off.
My advice. Full length size. Use a small base die. Use Wilson type cartridge headspace gages and full length size to gage minimum. Use the least sensitive primers out there, which are most likely to be the CCI#34 “Mil Spec” primers. Do not use Federal primers.. Seat all bullets magazine length. Never seat bullets to touch the lands. Use a SLED when single loading.
My slamfires were with match rifles and brass fired in military chambers. Brass must be sized smaller than the chamber. There should be absolutely no resistance to bolt closure. The reason is, that blasted free floating firing pin taps the primer when the bolt slows down. Standard sizing dies will not size big bloated brass enough to use in commercial type chambers. May not even be able to size big bloated brass in military chambers. Small base dies at least give more reduction.
I was able to talk to a number of people who had slamfires. Every single target shooter I talked to who ever had a slamfire used Federal primers. Which includes me. That primer is too sensitive. The best primer in the old days was the nickel plated WLR. Unfortunately in 1999 Winchester redesigned their primers and made them more sensitive. Recently I saw a post where someone had a slamfire with the brass WLR.
CCI seems to make the most insensitive primers, hear lots of complaints on these forums from folks who have out of tolerance firearms, they can’t light them off. Which is great for Garand users. I recommend CCI #34, and if you can’t get that, use CCI standard.
All primers should be seated by hand and visually verified that they are below the case head.
The Garand was type standard classified in 1936. That was a long time ago. Most off the shelf ammunition is too hot for the rifle. A lot of powders are inappropriate for the gas system of the rifle. I believe the first choice of powders is IMR 4985. Then next H4895, AA2495 (I used kegs of this stuff), and if you like a ball powder use AA2520. I think IMR 4064 may be a bit on the slow side for a Garand, but I have not used enough of that to form any intelligent long term conclusions. Basically a powder with a 4895 burn rate is appropriate for this gas system. A little faster is OK, a little slower may not, a lot slower is bad.
I have used a load of 168 grain Sierra Match, 47.0 grains IMR4895, LC cases, and CCI#34 primers OAL LT. 3.300 for years. This is a great target load, and is full power for the Garand.
With a 150 SMK I have used 47.5 grains IMR 4895, LC cases, CCI#34, OAL LT. 3.290”
My rule of thumb is keep the 168’s at 2650 fps or less. The 150 grain bullets 2700 fps or less. I probably hot load the 175’s because I have used 47.0 grs IMR 4895 with them. But I finally settled on the 168’s for across the course work so I don’t think I damaged anything. It does not hurt anything to cut my loads by a half grain or more.