Quick question: switched from 20" 5.56 upper to a 16" 300 BLK, which buffer needed?

[Jumbi]

Quick question: switched from 20" 5.56 upper to a 16" 300 BLK, which buffer needed?

I think I need to switch to a carbine buffer, is this correct?

[ThinkKrink415]

Is your lower receiver extension rifle or carbine length?

My 16”, pistol gas length 300blk ran with an H2 buffer.

[Jumbi]

It is standard rifle length
The rifle started as a spec 20" 5.56

[Jumbi]

I think I would like to drop in one these sound mitigation buffers ( I like quieter )

https://armaspec.com/ar-15-parts/buffer-springs/sound-mitigation-buffer-tm/sound-mitigation-buffertm-smbtm-gen2.html

Which weight would you suggest?

[ar15barrels]

Quick question: switched from 20" 5.56 upper to a 16" 300 BLK, which buffer needed?

It is standard rifle length
The rifle started as a spec 20" 5.56

Leave the A2 buffer and spring in the A2 buffer tube.

Do NOT run a carbine length buffer and spring in an A2 buffer tube without a conversion spacer to take up all the extra length.
A carbine buffer/spring in an A2 tube without the conversion spacer will damage the reciever when the gas key strikes the charging handle and the charging handle latch rips the charging handle latch cut from the back of the receiver.

[deadcoyote]

For what it’s worth I run an H2 weight and standard spring in my rifle length tube, with a 16” BCM upper with carbine length gas. It runs supersonic and subs reliably. Never had a stoppage.

[Jumbi]

Thank you. I will try it as it is with the original A2 buffer and spring

[NoHeavyHitter]

I'm clearly "not enough of an expert" so, this is why I carry at least one buffer of each of the common weights. Once I'm out in the field (and testing or helping someone test their new AR) I find that it's extremely useful to have extra parts on hand. More often than not, I'm able to get someone working or at the very least pointed in the right direction.

Given the costs of range trips + distance traveled, it can be expensive to test guns that you're not certain will run. Having spare parts to swap out goes a long ways towards minimizing fruitless (and costly) testing sessions.

Consider seriously bolstering your spare parts inventory, as it will likely save you money in the long run.

Sorry that his information is unlikely to help much in this instance... I mention it to help anyone willing to listen for future testing.

[Jumbi]

Thank you for this. Very good advice.

I'm clearly "not enough of an expert" so, this is why I carry at least one buffer of each of the common weights. Once I'm out in the field (and testing or helping someone test their new AR) I find that it's extremely useful to have extra parts on hand. More often than not, I'm able to get someone working or at the very least pointed in the right direction.

Given the costs of range trips + distance traveled, it can be expensive to test guns that you're not certain will run. Having spare parts to swap out goes a long ways towards minimizing fruitless (and costly) testing sessions.

Consider seriously bolstering your spare parts inventory, as it will likely save you money in the long run.

Sorry that his information is unlikely to help much in this instance... I mention it to help anyone willing to listen for future testing.

[code_blue]

You could just leave your existing rifle buffer system and try it that way. You don't "need" to change to a carbine buffer system, but if you intend to change to have an adjustable stock then yes, a full carbine buffer system (receiver extension, buffer, buffer spring).

There's a lot more to tuning your action, but I'd try H1 or H2 carbine buffers for 300 BO assuming you're running supersonics. Randall is here, so I'm sure he'd be the best person to get info from.

[Jumbi]

I'm going to be shooting mostly subsonic 200+ gr

I'll just try out the original A2 buffer setup when the local range opens up again.

Thank you everyone for the advice

[Jumbi]

Leave the A2 buffer and spring in the A2 buffer tube.

Do NOT run a carbine length buffer and spring in an A2 buffer tube without a conversion spacer to take up all the extra length.
A carbine buffer/spring in an A2 tube without the conversion spacer will damage the reciever when the gas key strikes the charging handle and the charging handle latch rips the charging handle latch cut from the back of the receiver.

Thank you for this!!

[deadcoyote]

I'm going to be shooting mostly subsonic 200+ gr

I'll just try out the original A2 buffer setup when the local range opens up again.

Thank you everyone for the advice