Buffer Weight Question

[R6436]

At work so I don't have a lot of time to research into past posts so I apologize up front if this is an overly discussed topic and thank you for your understanding.

I am recently looking into switching away from my M-16A2 style fixed stock on my precision rifle and am considering either an FRS-15 stock or a Hera Arms CQR P90 style stock. The potential issue I am seeing is they both use carbine buffers. In the past two years the only times I have had any issues is when using carbine buffers.

Which carbine buffer/weight would be best to use for a 20", 5.56mm rifle length gas system on a 20" 1:8 barrel? The same lower would also be potentially used with a .300AAC, 16" barrel with carbine length gas system both non-suppressed and eventually suppressed.

Any suggestions and/or personal experience would be extremely appreciated.

 

[bab029]

I'm looking into this for a spr-ish build i want to do. There's a thread in here that I started to get som input on that. Consensus is that a rifle length will provide the best shooting rifle possible for the rifle gas system, especially suppressed. I do want a collapsible stock, for lop adjustment shooting alternates, from a vehicle/atv and prone. For this I see two options: (1) the VLTOR A5 system which uses a rifle spring and proprietary buffer (look at BCM for a kit) and (2) see if I can use a lighter recoil spring and a heavy buffer to mimic this feel. For a from-scratch build, I'm probably going to pony up for the a5.

This stuff is all about compromises. I don't think you'll have problems with the 300 BO, it's a low pressure cartridge with a big bore so the pressure drops off pretty quick. But I don't have any practical experience here, all hypothetical.

 

[R6436]

Thanks for the input! I will keep the A5 system in mind as a possibility. The frustrating thing at this time is I can't find any information from Hera Arms as to whether or not an A5 tube would be compatible. Until first thing this morning I couldn't even find confirmation that their CQR stock used a carbine buffer system. I realize collapsible stocks are here to stay, but I wish there were more fixed rifle length stock options. Oh well, this old dog isn't against learning new tricks

 

[R_Swanson]

If you want to use 1 lower with multiple uppers I would run adjustable gas blocks. Thats what I do.

 

[hlee]

I think R Swanson hit on the winning suggestion. Use a buffer and spring that will work with all of your upper assemblies. Use adjustable gas blocks on your upper assembles to tune them to function reliably with the lower.