Garand Gas Pressure & Ammo

If you want to evaluate & compare commercial ammo vs mil spec ammo in the Garand, here is some decent reading and data.  It is also about selling a product, but I found the article informative.

One easy bottom line for me (that I already knew) - avoid commercial ammo with 180 gr and heavier bullets.  Meanwhile, stories about what ammo will damage the operating system are sometimes overblown (pardon the pun).

From a company selling a product.......Take it with a grain of salt.

Subject has been beat to death. Do a search

Buy Surplus M2 ball or Commercial Clones or roll your own.

Instead of buying a $50-100 ported PIA Gimmick plug ...Spend $8 on a good op-rod spring and just avoid Super Hot Premium heavy bullet commercial Hunting ammo.

You can safely shoot 180gr loads in Garands if they are loaded for Garands with correct powder. Tons of 180 SMK and Even 190 SMK's have been shot by highpower shooters through M1's back in the day along with Millions of M72 Match ammo with 174 gr bullets. Its not the bullet weight its the powder burn rate.

Ok yeah right grain of salt, but the data and what they report is reasonable.  

The main issue is volume of gas which is related to volume of powder, that is slow powders requiring a higher volume to achieve the same velocities as powders such as IMR 4895, running the risk of exceeding specs.

However there are commercial ammo that will work and will not harm the system.

I have been running one of those plugs in my Garand for several years now. seems to be working fine as my gas rod is still working great.