I'm ordering a barrel for my recce build soon. I will be shooting MK262 Mod 1 ammo exclusively. My plan is to order from Compass Lake, Krieger 7.7 twist, CLE Match chamber, midlength gas, 16" recce contour, and I'm sending them my Youngs MFG bolt for fitting. Anything you guys would change? Thanks
- Thread starter nl12
- Start date
Sounds like you have it all figured out. I wouldn't change anything.
Leave it just as you've got it!
The only thing that would give me pause or otherwise make me think twice would be the chamber selection. The CLE/AMU hybrid match chamber is great for heavier match loads, most specifically single-feed 80gr SMKs at around 2.500" COAL. That particular chamber really isn't necessary or particularly better suited to 77gr SMKs/MK262 Mod 1 than a standard Wylde chamber or any number of other options, but it should serve you well regardless. Just something to consider and you might mention your intended, dedicated round for the barrel and see if Frank (most likely Bunny is who you'll talk to) have any thoughts/suggestions as to what the most "ideal" chamber would be if not the CLE/AMU chamber.
The only thing that would give me pause or otherwise make me think twice would be the chamber selection. The CLE/AMU hybrid match chamber is great for heavier match loads, most specifically single-feed 80gr SMKs at around 2.500" COAL. That particular chamber really isn't necessary or particularly better suited to 77gr SMKs/MK262 Mod 1 than a standard Wylde chamber or any number of other options, but it should serve you well regardless. Just something to consider and you might mention your intended, dedicated round for the barrel and see if Frank (most likely Bunny is who you'll talk to) have any thoughts/suggestions as to what the most "ideal" chamber would be if not the CLE/AMU chamber.
OP,
I have a full heavy/fluted 18" SS 1x7.7 Krieger/CLE 5.56MM chamber rifle length gas system barrel. Frank White thought that their CLE 5.56MM chamber was best suited for the 77gr. SMK based factory BHA MK 262 MOD 1 cartridge or equivalent 5.56MM 77gr. SMK handload. But things do change so ask Frank about what current chamber type is best suited to your needs. Mine shoots the factory MK 262 MOD 1 or equivalent 77gr. SMK handload very well, it shoots the mag-length BHA 5.56MM 77gr. SMK AMU load a little better than MK 262, and it shoots the over-mag-length 5.56MM pressure 80gr. VLD very well at the recommended COAL of 2.390" for that chamber. Only thing I should have looked into was Frank's thoughts on a pin-on adjustable gas block for suppressor use. Other than that, no change desired. Good luck! And be sure to post some groups after you get your barrel.
I have a full heavy/fluted 18" SS 1x7.7 Krieger/CLE 5.56MM chamber rifle length gas system barrel. Frank White thought that their CLE 5.56MM chamber was best suited for the 77gr. SMK based factory BHA MK 262 MOD 1 cartridge or equivalent 5.56MM 77gr. SMK handload. But things do change so ask Frank about what current chamber type is best suited to your needs. Mine shoots the factory MK 262 MOD 1 or equivalent 77gr. SMK handload very well, it shoots the mag-length BHA 5.56MM 77gr. SMK AMU load a little better than MK 262, and it shoots the over-mag-length 5.56MM pressure 80gr. VLD very well at the recommended COAL of 2.390" for that chamber. Only thing I should have looked into was Frank's thoughts on a pin-on adjustable gas block for suppressor use. Other than that, no change desired. Good luck! And be sure to post some groups after you get your barrel.
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you are thinking of a different chamber than CLE normally uses. The regular CLE chamber is shorter than a wylde chamber. You could not put anything 2.5" coal into their chamber. A person would have to specifically ask for whatever a CLE/AMU chamber, i imagine he just reams the throat a little longer on this normal reamer. The regular CLE chamber is perfect for mag length bullets.
You could be correct, but to the best of my knowledge, I thought that the "CLE Match" chamber was the same as the CLE/USAMU chamber which is specifically throated for single-feeding the considerably longer 80gr SMKs for 600yd comps which won't work at mag-lengths in the AR. It is NOT the "CLE Chamber" which is a modified Wylde. Although the CLE Match is supposed to work well with the lighter/shorter match pills as well (at least the ones that aren't prone to problems with a slgihtly longer jump), I'd be damned sure to ask before assuming that you have got the "best" chamber specs for the job.
To that end, OP...best to confirm anything/everything with the fine folks at CLE before you order just so you are all on the same page as to exactly what you are getting and whether its the best option for you and your stated goals with your particular rifle/ammo.
OP,
I am home now and have access to further information. Here is a typical 5 shot group firing factory BHA MK 262 MOD 1 SECONDS off a somewhat shaky wooden bench at 100yds. The mag-length BHA 77gr. SMK AMU load is about 80 FPS slower than the MK 262 loading & has grouped as tight as the mid 3s from the same barrel fired off a proper concrete bench in trigger pull conditions. When firing this barrel with either BHA MK 262 or AMU loads, I am the weak link. The barrel clearly wants to shoot well.
18" full heavy/fluted SS Krieger/CLE 5.56MM MATCH chamber barrel with M4 can firing 77gr. SMK based 5.56MM BHA MK 262 MOD 1 SECONDS (LOT: BLH06J123-001) at 100yds.: MV 2825 FPS 5 shot average
I am home now and have access to further information. Here is a typical 5 shot group firing factory BHA MK 262 MOD 1 SECONDS off a somewhat shaky wooden bench at 100yds. The mag-length BHA 77gr. SMK AMU load is about 80 FPS slower than the MK 262 loading & has grouped as tight as the mid 3s from the same barrel fired off a proper concrete bench in trigger pull conditions. When firing this barrel with either BHA MK 262 or AMU loads, I am the weak link. The barrel clearly wants to shoot well.
18" full heavy/fluted SS Krieger/CLE 5.56MM MATCH chamber barrel with M4 can firing 77gr. SMK based 5.56MM BHA MK 262 MOD 1 SECONDS (LOT: BLH06J123-001) at 100yds.: MV 2825 FPS 5 shot average
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From the test thread. Here is a 5 shot using new Black Hills 77gr OTM (mk262 mod 1) through a CLE Krieger 1:7.7 20" with a CLE match chamber. 100 yards prone off a bipod and rear bag. Speed was 2808fps average so the 16" will be a little slower but still plenty of get up and go.
This measured .36 MOA
As for the lighter stuff, it doesn't do too shabby with Fiocchi 40gr vmax .223 either.
This measured .36 MOA
As for the lighter stuff, it doesn't do too shabby with Fiocchi 40gr vmax .223 either.
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not that it's a big deal but there is only one CLE match chamber. Frank designed it in the 90's and it is not a modified Wylde. They are different in most every area. The AMU has modified their chambers to push the oal of 80 grain bullets to much longer than most people do because they want as much powder in the case as they can get to give them a little extra push for 600/1000 yard matches. The downside to that is you would losing about .060 of barrel life, it's a lot. The AMU chamber works just fine with mag length bullets, they have been winning competitions for years with it, you have to shoot 200/300/600 with the same rifle so the chamber works just fine. They just wanted a little extra edge at 600 and don't care about barrel life, since we buy their barrels!
The CLE match chamber will have a 80 grain SMK at about 2.435", a Wylde is about 2.475", AMU is about 2.5". See the difference. They all have their merits and demerits. I just got off the phone with Bunny at CLE because I have a barrel there now for profiling and chambering, this is all confirmed by her. Hate to waste her time with this stuff but I just wanted to confirm they didn't change anything. She laughed, said "if it ain't broke, don't fix it". This is my third CLE barrel with their chamber.
Thank you all for the shared wisdom!
