buffer weight

[Koda]

First post and brand new to the Grendel, I thought I would just dive right in here with a very basic question but first a very quick background.
Built my first AR Grendel, 20in bbl. Still unfired as I wait for the stock to arrive. Use will be deer hunting and I plan to handload for this right from the start. I'm familiar with the AR platform a little bit but never had an adjustable gas block. I ordered a Geissele carbine length buffer tube assembly that comes with an H1 buffer.... but then I wondered if the Grendel gasses more than a standard 223/556....

So my question is there a correct buffer weight to work with the Grendel?

[Harpoon1]

First post and brand new to the Grendel, I thought I would just dive right in here with a very basic question but first a very quick background.
Built my first AR Grendel, 20in bbl. Still unfired as I wait for the stock to arrive. Use will be deer hunting and I plan to handload for this right from the start. I'm familiar with the AR platform a little bit but never had an adjustable gas block. I ordered a Geissele carbine length buffer tube assembly that comes with an H1 buffer.... but then I wondered if the Grendel gasses more than a standard 223/556....

So my question is there a correct buffer weight to work with the Grendel?

[LRRPF52]

[Koda]

I'll have to check my settings because I didn't get email notifications.

Appreciate the replies. I kept searching the web and concluded I could run a carbine length buffer assembly with my rifle length gas system. I'm still not certain if the Grendel produces more gas than a 223 but with an adj gas block I don't think it matters. The only downside it I have to remove the mlok forearm to adjust the gas block.
Still unfired but cant wait to play with the new rifle. Today I ordered the bullets I want to hunt with and will get right into load development after they arrive.

[dpete]

The only downside it I have to remove the mlok forearm to adjust the gas block.

Have you looked at using a ball headed allen wrench screwdriver to get at the gas block? You may be able to get it through one of the M-loc slots from the side.

[603Country]

When I bought a Grendel upper from a fellow here, I wanted to use the 5.56 lower I already had. Having the same questions you do, I discussed it with the local and knowledgeable gun shop folks who deal primarily in ARs. They suggested that the 5.56 lower/spring/buffer should work fine, so I tried it. It worked fine. Not exactly a technical answer, but just an experience. I used the Grendel like that till I had a new Grendel lower assembled.

[Koda]

Have you looked at using a ball headed allen wrench screwdriver to get at the gas block? You may be able to get it through one of the M-loc slots from the side.

I have, its too far behind one of the mlok ribs.

[LRRPF52]

I'll have to check my settings because I didn't get email notifications.

Appreciate the replies. I kept searching the web and concluded I could run a carbine length buffer assembly with my rifle length gas system. I'm still not certain if the Grendel produces more gas than a 223 but with an adj gas block I don't think it matters. The only downside it I have to remove the mlok forearm to adjust the gas block.
Still unfired but cant wait to play with the new rifle. Today I ordered the bullets I want to hunt with and will get right into load development after they arrive.

[Klem]

Koda,

You could drill a tiny hole in the rib directly above the adjustment screw, no wider than the driver needed to adjust the gas. To conceal the shine tape over or touch it up with paint.

[Koda]

This makes sense. Mine is a rifle length system. I'm guessing I wont have any issues but its good to get some confirmation...

[Koda]

Koda,

You could drill a tiny hole in the rib directly above the adjustment screw, no wider than the driver needed to adjust the gas. To conceal the shine tape over or touch it up with paint.

Ive thought about this but decided not to. The handguard has a custom logo and appears to be custom to a custom upper as the geometry lines match. Not that a handguard is that special, but I dont want to modify it since its specific to the build brand.

[rickt300]

I generally set up all my lowers with A4 stocks and of course the rifle buffer set up. No problems ever with any upper so far.

[Bonas]

I use standard carbine buffers. With adjustable blocks, I tune the block with the handgaurd off. The adjustable blocks I use can be adjusted with my handguards on, but it's easier to tune it the first time with them off. I restrict flow on the weakest ammo I'm likely to use until I get a failure to lock back on an empty mag, then open it back up until it locks back. The handgaurd goes back on, and I rarely touch them after that.

[Koda]

I use standard carbine buffers. With adjustable blocks, I tune the block with the handgaurd off. The adjustable blocks I use can be adjusted with my handguards on, but it's easier to tune it the first time with them off. I restrict flow on the weakest ammo I'm likely to use until I get a failure to lock back on an empty mag, then open it back up until it locks back. The handgaurd goes back on, and I rarely touch them after that.

from what Ive read this is what I'll do. I went with a carbine H1 buffer by Geissle.

[Koda]

Update: today I took the new Grendel out for its maiden voyage. I loaded up a pressure ladder of 97gAbsolute Hammers over A2520 powder. I ran 13 rounds getting up to 2788fps safely.

I kept adjusting the gas screw out until it was barely holding on but could not get the bolt to lock back on the empty mag.

Im using a Geissele carbine buffer assembly. I suspect the culprit is their "Super 42" buffer spring, is "15% stronger" than a standard carbine spring.