Home Forums Hunting & Shooting AR and Tactical Rifles 22", 8 twist, .243 LBC build.

What contour barrel did you use on this build and your longer .264 LBC?

The current 22" .243 LBC has a custom contour. It's between a light contour and a standard. It's a contour that Griz Precision uses.

My long .264 LBC is a 26" full bull contour. As far as I know only two 26" full Bulls were ever made by them for a AR. My guy that was great to work with at Black Hole has since left them and he's the one that did a barrel for me and himself.

Here's three of my 8 twist Black Hole .264 LBC barrels. All are 8 twist and rifle length gas, all are threaded 5/8-24.

Top 26" full bull
Middle 18" SPR
Bottom 16" custom "Hammer Flare" contour

Did some load development today with the 95gr Berger VLD Hunting bullet and some CF223. The load on the left looks like a solid load.

2999 FPS
SD. 5

.243 LBC
22"
8 twist Black Hole Barrel

Don't forget, get away from the chrono once you are happy with the speed area you are at. Results on paper trump ES and SD on the chrono every last time....

IE don't chase magic numbers, just shoot for groups.

I have three solid half MOA loads.

95gr SST's @ 2887
105gr A-Max @ 2801
95gr Berger Hunting VLD @ 2999

I really like the performance of the 6mm 95gr SST on deer but I have not taken any deer with the 95gr Berger VLD or the 105 A-Max. I have yet to work up a load with the 90gr Accubond in this rifle (.243 LBC) but I have shot a Mule deer with the 90gr Accubond in the 6x6.8 SPC chambering and it performed well.

The thing I find annoying with most wildcat AR's I have built is the curse of the first round slightly out. I lock the bolt to the rear, seat the magazine and and release the bolt. I have tried dropping a round in the chamber. Then releasing the bolt, then inserting the mag. I've tried riding the bolt with the charging handle for the first round. More often than not it puts that first round slightly out. Drives me crazy!

Got nothing to add except nice rifles and shootin smack!

Good to know you are happy, thats some good groups. I"ve never seen the 1st round issue, but then I don't have many ARs that are not 223.

RE the chrono, point was for load tweaking, ES/SD mean less in the long run than what paper tells you at your max distance. Disregarding things that start at 500-600 or so and head furhter out... then ES is an issue, but it will also show on paper targets as vertical spread.

I've yet to end up shooting the most promising load according to my chrono EVER....

Interesting thread, I never have worked with the Grendel, or any of its variants. Might be a fun build, after I get a couple of 5.56's finished

Bumping an old post for updates. Smack, now that you've had this 243 LBC for a while, do you have any more feedback or advice?

I'm thinking of putting one of these together now. I'll be starting from scratch on dies, components, bolt, barrel, etc, but it looks like I can use 6 PPC dies, and I'll probably go with a BHW 1:8 barrel. I'm thinking 20-24" but haven't pulled the trigger yet.

20"
1-9 twist
CFE223 powder was great
.243 LBC dies can be purchased from CH4D tool & Die. Great people!
Use ASC 6.8 SPC mags

Thanks for the feedback! Tried to contact you on the HuntWA board but no success - do you still sell BHW barrels? If so I'd like to find out some info from you on buying one. If not, other suggestions are welcome too.

Any rough estimate of velocity with a 20" compared to your 22" loads I quoted above? I'm leaning towards that 95gr VLD based on what I've read, hoping for close to 3000 fps. I do like the idea of a slightly shorter 20", and may go with a standard or lighter profile instead of a heavy barrel. Open to suggestions there. I'll use an ACS-L stock and hope to keep it at 10-11 lb max.

Just curious on your 1:9 twist recommendation - does that give up anything compared to 1:8 with 105/107gr bullets?

Good info on the dies, powder, and mags. Already have that powder and several of those mags for 6.8 based wildcats, so that works out well. Thanks again.

Love it when a plan comes together; even better when you get lucky right from the start. That 32.4gr load shows promise in my rifle too... Thanks for sharing it, Smack!



This is only the second group ever with this rifle, 5 shots at 100, prone with bipod and a rear bag. Those are 1" squares on the target, group size is right at .500".

I got my 243 LBC barrel from Black Hole recently (they were actually pretty fast on this one, only 4-5 weeks) and assembled it in a thermofit BCM upper. I went with a 1:8 twist, standard profile, very similar to Smack's barrel above but 24" length. My goal was 10 lb with scope, sling, and an empty mag; this one ended up at 9 lb 14 oz.

Do I need to call CH4D for dies because I didn't see them listed on their sight. What bushing are you using?
I'm planing on getting a 22" barrel, 1-8tw, Aero upper and lower.

I emailed CH4D and they did have a couple sets left, but I ended up just using some 6mm PPC dies instead, no issues with that. I'm not using bushing dies.

Y'all are killing me with these. I want one but wish they offered a +2" gas system.

From shooting mine, with a properly adjusted gas block - I don't see any need for a +2" gas system. Rifle length is fine, just tune the gas correctly.

IMO people put way too much emphasis on AR gas system length, and not nearly enough on tuning the gas.

I agree that tuning is important but there is a reason you don't have a carbine or pistol gas length gas system on that long barrel of yours.

Sure there's a reason, but it's a lot less important than many online seem to think. Gas metering (either port size or gas block adjustment) plays a much bigger role in bolt timing than port location.

As I said, mine runs fine with rifle length gas when properly adjusted. Why do you think you need +2"?

I'm sure it does run just fine. Why do they offer mid and rifle on a 20" .243 LBC? Because people want it and either will work. Why do the stop offering mid length on a .243 LBC at 22"? Because it's not optimal. Several guys I shoot with who shoot the 6mm Fat Rat and V Fat Rat use it with longer barrels (24 to 27" and one 27" with a suppressor) and +2 gas with great results. You even see plus gas on .223 Match rifles. I'm not saying it is a requirement for a .243 LBC anymore than it is a requirement to use rifle length vice mid on an 18" .223 Wylde but I'm saying it might not be optimal to use the shorter gas path. Where is the gas port on an M1 Garand? Was it a terrible plan?