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3/1/2007 1:09:52 PM EDT
My next build is a lightweight midlength A2 KISS rifle.

CMMG makes an upper for this, but the twist is 1/12.  I'd like to shoot heavier loads out of this rifle, and I can't find any other midlength LW uppers from the dealers I usually work with.  Any suggestions?  Could I order it custom from Adco or someone like that and keep it in the $600 range?

Thanks.
3/1/2007 5:52:24 PM EDT
[#1]
cmmg barrels are 1/7.
3/1/2007 6:01:26 PM EDT
[#2]

Quoted:
cmmg barrels are 1/7.


The 16" LW midlength is 1/12.
The 14.5" LW midlength w/perm FH is 1/7

I checked to make sure it wasn't a misprint on the site. They confirmed that 1/12 is a throwback to the retro style barrels that many people requested. I personally did not want a 1/12 twist or a 14.5" with perm FH, so I passed. I thought 1/12 was more for a 20" barrel, but apparently not.

If they would have had the 16" in a 1/7 twist, I would have been all over it. Instead, I went LW carbine from Del-Ton. Too bad Del-Ton doesn't have a LW middy.

3/6/2007 5:54:47 PM EDT
[#3]
I can profile any mid-length barrel into a lightweight.
Then you can have the exact configuration of twist rate and feedramps that you need.
3/6/2007 6:04:45 PM EDT
[#4]

Quoted:
I can profile any mid-length barrel into a lightweight.
Then you can have the exact configuration of twist rate and feedramps that you need.

Is this possible with pinned FSB's?  
3/6/2007 6:22:31 PM EDT
[#5]

Quoted:

Quoted:
I can profile any mid-length barrel into a lightweight.
Then you can have the exact configuration of twist rate and feedramps that you need.

Is this possible with pinned FSB's?  


I remove the FSB before profiling.
3/6/2007 7:20:01 PM EDT
[#6]

Quoted:

Quoted:
I can profile any mid-length barrel into a lightweight.
Then you can have the exact configuration of twist rate and feedramps that you need.

Is this possible with pinned FSB's?  


I can just see that in the lathe:

Wack wack wack wack wack wack...

3/6/2007 8:41:48 PM EDT
[#7]

Quoted:

Quoted:

Quoted:
I can profile any mid-length barrel into a lightweight.
Then you can have the exact configuration of twist rate and feedramps that you need.

Is this possible with pinned FSB's?  


I remove the FSB before profiling.



Let me rephrase that.

Does this produce satisfactory results when taking a barrel that previously had a pinned FSB, and then attaching a new .625" size pinned FSB?
3/7/2007 3:17:53 AM EDT
[#8]
If you are going to have a barrel reprofiled, I would try to find another 1/7 twist barrel, CMMG is already pricey. When you add on the cost of the reprofile, it would be quite expensive. I'm not sure who makes 1/7 twist barrels, though. If you don't mind 1/9, I would get a Del-Ton upper and have it turned down to a LW profile. I couldn't find too many midlengths in general let alone a 1/7 twist. RRA makes a 1/9 midlenght also. I imagine with the reprofiling on either of these barrels, you would still be under the cost of a CMMG. I don't shoot heavy bullets in mine, the 62Gr m855 is the heaviest I have shot. I understand that 1/9 will go to around 68 or 69Gr.
If you really want 1/7, then buy the medcon barrel and have it turned down or buy the 14.5" lw midlength with permanent fh from CMMG.
If 1/9 is good, then go with Del-Ton or RRA and have it turned down.

I went lightweight carbine from Del-Ton on my second build because CMMG has about the only lightweight midlength available chambered for 5.56/chrome lined and I didn't want 1/12 either. I am hoping that barrel manufacturers will catch on and offer more 18" and 16" midlengths in standard as well as lightweight, for a reasonable price. I read a lot of posts that people really like the midlength, so they will have to catch on someday soon.
3/7/2007 7:48:48 AM EDT
[#9]

Quoted:
Does this produce satisfactory results when taking a barrel that previously had a pinned FSB, and then attaching a new .625" size pinned FSB?


Yes.
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