Quick question regarding proper buffer selection for the Grendel round.

So I've ordered the following upper:

https://palmettostatearmory.com/catalog/product/view/id/33781/s/psa-20-rifle-length-6-5-grendel-1-8-stainless-steel-15-m-lok-upper-with-bcg-ch/

And paired it with the following lower:

https://palmettostatearmory.com/psa-ar-15-complete-lower-magpul-ctr-edition-fde-no-magazine.html

I took the lower to local gunsmith who advised me that I should change out the tube, spring, and buffer in this lower as the upper is rifle length while there is a carbine buffer in the lower. I have not fired the weapon, and don't want to if I'm going to break parts.

I have pretty much the same upper setup in 6.8 spc, and don't have issues (as far as I can tell).

Googling the answer has me more confused than before I started, so I'm seeking advice.

No risk of breaking anything. Give it a try.

CactusThomas said:

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No risk of breaking anything. Give it a try.

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Not sure if serious

So the question is.

Should you change out tube, spring, and buffer?

Short answer. It's not necessary.

Sounds like the gunsmith is trying to sell you stuff you don't need.

That being said, I really don't know... someone smarter than me can chime in.

It is not necessary to mate your rifle upper with a rifle buffer tube/spring/buffer. It will run and cycle just fine.

The reasons for going to a rifle stock configuration are:
- Softer recoil impulse
- Cycling issues when running a suppressor and/or subsonic ammo, or hot reloads.
- Longer length of pull desired

If none of those apply to you then don't change anything.

I'm running a plain ol' buffer kit on my .450 bushmaster. Haven't broke anything yet (besides my shoulder). I'm sure you'll be fine with the 6.5

I don't see what difference it would make to run a rifle length upper with a carbine buffer tube. If the recoil and ejection is a little rougher than it could be, you could always just run a heavier buffer and/or stiffer spring. I have a rifle length upper mated with a carbine buffer tube on my Grendel setup with an H2 buffer and adjustable gas block. No issues here.

Keep the buffer you have and run an adjustable gas block.

ttha_aggie_09 said:

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Sounds like the gunsmith is trying to sell you stuff you don't need.

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I agree. Rifle uppers can be run on carbine buffers.

There is a very slight chance of some reliability issues, but if you have issues, then you can always adjust buffer weight, springs, etc as needed, but it's been done in stock form by lots of people, including me.

I toyed around with a 'Mericanized Canadian C7ish thing for a bit. The 20" 5.56 upper ran just fine on a standard carbine buffer.