Cutting a 20" to 18"?

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[ARCHIVED THREAD] - Cutting a 20" to 18"?

Posted: 7/26/2003 9:46:45 AM EDT

All this talk of 18" barrels has me tempted to whack off the nose-end of my rifle. Would there be any need to change the size of the gas port?

The positives seem well represented in other posts. Any other potential ill effects, other than costing money to have done by a competent 'smith? Would the change in dwell time have any adverse effects?

Posted: 7/26/2003 10:09:58 AM EDT

[#1]

I didn't have to change the gas port size on mine. (I went from 24 to 18)

No problems on mine.

Posted: 7/26/2003 8:50:05 PM EDT

[#2]

I haven't had any problems with mine, and I did it at home with a hacksaw and one of these [url]http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=628[/url]

Posted: 7/28/2003 4:52:19 PM EDT

[#3]

Caffino,

There is a good article in the July 21st issue of Shotgun News about cutting and crowning.

Posted: 7/28/2003 5:08:00 PM EDT

[#4]

I like the brownells tool idea better than the shotgun news wood screw idea.

Posted: 7/28/2003 6:47:59 PM EDT

[#5]

Thanks for your responses. If no one is reporting problems, I have no reason to not drop a little weight off the front of my rifle.

Since the upper is going to be with KKF for other work, I'll ask him to trim it. If the rifle wasn't heading out there, I would probably cut it myself.

Posted: 7/28/2003 9:41:32 PM EDT

[#6]

Kurt did one of mine. He does good work and did not have to adjust the gas port.

Posted: 7/29/2003 9:03:56 AM EDT

[#7]

What type of tools would you need to keep the bit/barrel centered when putting on the new crown?

Posted: 7/29/2003 2:01:47 PM EDT

[#8]

Quoted:
I like the brownells tool idea better than the shotgun news wood screw idea.

View Quote

yeah, that did surprise me as well.

Posted: 7/29/2003 3:56:25 PM EDT

[#9]

The Brownells tool has a precisely sized bit that fits into the bore to keep the cutter aligned. It comes with a t-handle to turn the cutter by hand but there's also a drill attachment to use the cutter in a drill press. When you order the cutter you specify the bore size that you need and you can also order additional bits for other bore sizes. I noticed when I posted the link that they only list an 11 degree cutter for cutting target crowns, but I bought a cutter that cuts square to the bore.

Posted: 7/30/2003 4:19:17 AM EDT

[#10]

I used the brownells cutter when i cut down my chrome-lined FAL barrel. The problem i had was when i started cutting that chrome no matter what preasure i used i got chatter (yes i used cutting fluid). So i finished it off using the booger picking method, a marble with valve lapping compound, which i presume is basically the same as the SG approach. I did use the muzzle facing (?) cutter to square the end of my barrel first.

So based on my limited experience i would say get the crowning tool if you don't have a chrome lined bore, save your money and get to picking if you do.

Posted: 7/30/2003 9:28:09 AM EDT

[#11]

Curt, as usual Brownells has a tool for that too. Bascially a brass rod that fits in a drill. The end is rounded off and you put a little polishing compound on it. I didn't use it but it is there.

[ARCHIVED THREAD] - Cutting a 20" to 18"?

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