Grendel Short Barrel Group Buy Orders

[cory]

I'm going with an adjustable and a Spikes T2 Buffer/Spring. I'd like a JP Silent Capture Buffer, but I just can't justify the upgrade.

[Variable]

I'm no expert not even a novice in cerakoting, but I wouldn't think it would. They aren't bead blasted, but have you ever cleaned an NiB or Nitrided Carrier? The surface is extremely smooth.

Ahhh, the dimple fluted barrels that Mark did are bead blasted. He blasted them after dimpling, and then sent them out to nitride with the others. Mine only looks kind of shiny in the pic because they wiped oil on it. It's not a super aggressive tooth, but it is definitely a matte bead blast surface.

[Variable]

are you guys going with adjustable gasblocks? if not, what buffer?

SLR Sentry 7 adjustable for me (actually the Ti version for the weight obsessive).

[Drift]

I really like the dimples. Next time I get a barrel for a bolt action I think I'll get it dimpled

[cory]

Ahhh, the dimple fluted barrels that Mark did are bead blasted. He blasted them after dimpling, and then sent them out to nitride with the others. Mine only looks kind of shiny in the pic because they wiped oil on it. It's not a super aggressive tooth, but it is definitely a matte bead blast surface.

Sorry I didn't mean the barrels weren't bead blasted, I was referring to the BCGs I was using as a comparison.

[cory]

I really like the dimples. Next time I get a barrel for a bolt action I think I'll get it dimpled

I was surprised at how much I liked the dimple fluting. I don't think I'd do it on a longer barrel, but on another SBR barrel I might just.

[cory]

Is anyone planning to pin their gas block to the barrel?

[Bwild97]

Range Report W/ the 12.5" group buy Lilja barrel.

After assembling the upper I checked the chamber measurement against all my dummy rounds and the bolt whent into battery on all, very happy!

150 yds
The scope I used is not going to be a permanent fixture to this upper, so I didnt bother with zeroing the scope. Shot up all my leftover loads to clear up brass. Overall I'm quite happy with the first groups!


This was a welcome surprise! If I remember correctly, someone said a short barreled Grendel was worthless, and respectable velocity was impossible!

[Adam Lilja]

2900 FPS? Am I reading that right?

[Bwild97]

2834 fps avg with the 90g TNT!! From a 12.5" brl.

[LRRPF52]

I'm looking at N133 data right now. AA shows a max load of 27.5gr under a 100gr Scenar.

Lapua shows a max load of 29.3gr under the 100gr Scenar, and 27.8gr under the 108gr Scenar.

32.0gr is pushing it with the 90gr TNT, but it's a more appropriate powder for that short of a bullet for sure. If you compare the 90gr TNT to the 100gr Scenar, they are very different bullets, so it looks like there is room to work with in charge weight above the 29.3gr load listed by Lapua.

What did the brass look like?

I would like to see your results with LVR under the 129gr ABLR.

[BluntForceTrauma]

Perhaps the 90 TNT has less bearing surface than the 100 Scenar?

[LRRPF52]

They both have a .400" bearing surface, but the 100gr Scenar is 1.24" long, whereas the 90 TNT is .910" long. They're totally different bullets for sure, and the 90gr TNT allows more room for case capacity, so pressure won't build as fast under it for those two reasons:

More case volume
Less weight

After talking with Mark, he said they've been seeing faster mv from the nitrided barrels as well, so there's that.

[Bwild97]

The VV133 loads are the loads I used for function testing since I had more of them than any of the other loads.

Gas block adjusted for the VV133


After I was satisfied with the functioning of the rifle I moved to group testing. I started with the 100g Amax over 29g of XBR. On the first shot the bolt failed to strip a round from the mag, 1 turn counter clockwise, problem solved. One more 1\2 turn ccw for good measure. The rifle performed flawlessly for the rest of the day. After group testing I setup my chrony to check velocity.

The VV133 loads with an extra 1 1\2 turn ccw.

[55Kingpin]

Any chance there is a spare barrel available?

I'd like to pick one up.

Thanks,
Chase