Range Report Finally Took My 6.5 Grendel Build for a Spin

[diggler1833]

I put a Grendel together a few months ago as a half range / half hog gun that will occasionally see some thermal work (whenever I can get Sellmark to fix my Thermion...I digress).

Rifle is an Aero receiver kit with Aero LPK. Trigger is a Larue MBT-2S. Barrel, BCG, and the rest of the upper components are all Wilson Combat...save for the CMMG SV brake I out on there since I took a photo of this rig. Barrel length is 20 inches.

Shot 10 rounds for break in with a middle of the road handload. 1-2 sighted in and cleaned, 3-5 initial group (MOA) and cleaned, 6-10 group (MOA again) and cleaned.

Shot it today at my 160 yard range (my back shop door to my pond berm). Yes, it's an unusual distance, but the math isn't too hard (watch, I screwed it up). Anyway, the first group was GTG with a cold bore a little far away, but still sub MOA. Group two barely above MOA, and the third group was pretty decent with just a hint of ejector swipe in 85 degree weather.

I'm not going to screw with it too much now. I'll retest the two best loads and then start playing with some of the Speer Gold Dots and SSTs that I have on hand to get a decent hog load.

 

[bobke]

Have same barrel, and it took about 75 rounds or so for it to truly shoot in. Have has excellent results with AR Comp and 123CC’s and 123 Sierra BTHP. 8208 and CFE work quite well also. Would be helpful to know your velocities vs POI for groups you’ve shown. Look for your barrel to continue to improve.

 

[diggler1833]

Have same barrel, and it took about 75 rounds or so for it to truly shoot in. Have has excellent results with AR Comp and 123CC’s and 123 Sierra BTHP. 8208 and CFE work quite well also. Would be helpful to know your velocities vs POI for groups you’ve shown. Look for your barrel to continue to improve.

Somehow I ended up with 16lbs of TAC and another 8lbs of 8208 XBR (and I still have 10lbs of CFE 223. I like the potential velocity with some of these ball powders like the AA2520 for hunting as my primary hog rig is a 6.8. Obviously the 8208 isn't a ball powder.

I'll probably try some of the extruded powders when I start shooting the match bullets again. I've only got two boxes of Nosler CC, so I might try some of Hornady 's stuff. I am done with the SMKs...their meplats are all over the place. I have had .017" OAL variation in my last box of 69gr. Not as horrible if loading for a bolt gun, but for mag length loading in an AR its completely unsat.

 

[bobke]

Totally get the issue with BTO variation-have seen up to .024 in Nosler CC seconds, so either sort ‘em or avoid ‘em. Have been working off of same lot Of 2000 123 Sierras and have not had any issue. You’re GTG with Tac and CFE. CFE seems to work best near its upper working range, and have gotten 2650 in a 24” Satern barrel with VG accuracy in summer heat, but approach cautiously. 2550 same load in 20” Satern.
Am keeping most of my WC 20” loads right around 2500 with VG accuracy using AR Comp in low 27ish range.

 

[Greg Langelius *]

I've 6.5G's in 20" and 24". I've tried several load development strategies, and my current one uses the Speer 6.5/120gr Gold Dot as an experiment in developing a multipurpose round.

I'm learning to like TAC and 8208, and have done a bunch of work with the 120 and W748.

The Grendel Bolt does not like hotloading; mine sheared the extractor when I ventured just barely above book max. I depended more on pressure signs than on book loadings and paid the price.

One sign that appeared and was missed was the additional sooting on the fired cases. It was apparently a symptom caused by attempting to extract while there was still pressure in the barrel. It happened with the 24" and I'm assuming the extra 4" of barrel length/dwell time exacerbated the issue.

The problem is behind me now; no more hot loads, the 24" has a JP Improved Grendel extractor now, and I'm reserving that rifle for testing with the Speer 90 TNT, hoping to reduce bore transit time that way.

The 20" shows promise, and during lockdown all the questionable loads were pulled down, and new try-loads with the 90 TNT/TAC, and 120SGD/8208 are waiting imminent ventures out to get things back up to speed.

These new ventures mark a complete break with the earlier projects.

Previously, the rifles were configured with collapsible stocks, and were a bit of a handful to shoot from the bench. Currently, they have all been converted to provide bench shooting ergonomics. The the collapsibles were replaced with Choate E2 stocks, all my AR's now have Luth AR Chubby Grips, and A2 stocks have had EGW Bag riders added. Adding those stocks also required A2 buffer assemblies, and the 308 got a JP 308 Silent Captured Buffer. Additional ergos, including BAD levers and 2-Stage triggers have also been added. The rifles; 2 6.5g's and a 308, all look pretty identical, and have the same ergonomic dimensions, with some extended LOP to deal with my extra height.

Oh; and they all now have Bushnell AR Drop Zone BDC scopes.

I'm estimating that the drops for the 6.5G and the 308 are close enough to use the 308 BDC reticle for the 6.5G. Testing with steel at 100. 200, and 300yd will confirm or deny this.

I figure it was a worthy use of the stimulus bucks and the enforced quarantine time. They do look a little bit like Buck Rogers with the E2 stocks, but...

Greg

 

[Greg Langelius *]

I finally got out to the formal range in Douglas yesterday, after waiting since Mid-March. The two Grendels and the PA-10 308 needed to be properly sighted in and function tested. They are sighted, function tested, and initial loads were tested.

No malfs of any kind. Zeroing took some time, but got accomplished. I had an issue with the BDC reticles not being on at the longer distances until I remembered that they needed to be set for maximum magnification, and then they were banging the gongs pretty regularly at 100, 200, and 300yd,.

The initial loads surprised heck out of me, that are all shooting pretty small. I'm gonna come back and confirm that and maybe test a few bracket loads to see if any improvement is possible.

It's great to have things work OK first time out. It's been a long wait.

Right now, the 24" Grendel is testing the 90 TNT load with IMR-8208XBR. I like it so much I'll do the bracket test, but really, it's good enough to be a keeper already. The 20" is using the 120 Gold Dot and W-748. It's also a good shooter, but I think we can get some improvement yet. The 308 168 Gold Dot and IMR-4064 also looks good, and for what I want, I doubt that load development will be necessary.

None of these guns are intended for competition, my accuracy demands are not strict (1MOA-ish is doable already), and I am getting a bit old for the strictest regimens of load development.

At this point the project is essentially complete, and can form the basis for working on groups for fun.

Greg