What considerations when reloading for semi-auto rifle

[firstater]

New to reloading and have just finished my first 100 rounds of .223 which will be used in my Bushmaster. 25.5 grains of Varget with 55grain sierra bullet crimped with lee factory crimp die. I have read through a couple of manuals and ABCs of reloading. They only seem to mention autoloaders briefly. A few articles I have read stress the dangers of handloading semi-auto and advise against doing it all together. Others don't seem to differentiate between reloading for gas and bolt action.

What do you do differently , if anything, when handloading for your auto-loader? Do you avoid reloading for some auto-loaders or do things differently for example M1A, FAL AK SKS Garand? Any special tools - gauges, dies or anything for reloading gas guns that are a must have?

 

[JDGray]

Just be sure to full lenght size, and everything else is the same. Powder charge is usually a bit lighter in gas guns, too

 

[earlthegoat2]

Sometimes you may need a small base die set as well just to increase feed reliability.

 

[steve4102]

I load for all my semi-auto rifles. Couple things that must be considered when loading semis, Always, always full length size you brass. Not only FL size, but make sure your die is set up correctly to allow for the proper shoulder bump.

The generic way is to raise the ram, screw the FL die into the press until it touches the shell holder, lower the ram and screw the die into the press 1/4 turn more. A better way is get a case gauge.

Here is a good article on handloading for service rifles.

http://www.exteriorballistics.com/reloadbasics/gasgunreload.cfm

 

[mallc]

Gas Autoloaders

Most common advise is:


1. Gas autoloaders have requirements that do not apply to bolt action rifles of the same calibers.

2. Always full length resize. I load .223, .308, 30-06 for several guns and have never needed a small base die. I use a case guage for checking the size, but you could also drop a resized, cleaned brass into the chamber to check fit.

3. Use a stout primer and make sure they are properly seated. There are reports of slam fire due to the firing pin striking a sensitive primer or one that's not been seated below flush. My only bad experience was with .223 loaded on a Dillon 650 with Winchester primers - primers were not properly seated. CCI #41 NATO are the most often recommended small rifle primer for gas auto-loaders. CCI #34 are the most often recommended large rifle primer for gas auto-loaders.

4. Varget is probably a bit hot for M1 Garand. Too much pressure, too fast will damage the operating rod. IMR 4895 is the most often recommended powder for 30-06 and .308.


Special thanks to Reloader Fred and Walkalong for patiently repeating best practices for loading specific ammunition until the rest of us get it memorized! You guys are great!

Hope this helps.
Scott