Gunsmithing @ AR15 and barrel experts. Barrel question?


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Full Member
Mar 16, 2012
Bucks County, PA USA
I was thinking of picking up a LT50 SS 18" Lother Walther mid-length gas in .223 Wylde 8 twist polygonal rifling. I want to either cut and crown it at 16.125" or cut to 14.5" and pin and weld muzzle brake. This state requires me to perm attach any muzzle brake on semi's regardless of barrel length or I would just go with a 16".

So my question is, what would need to be done to the gas port if anything. Is there a specific gas port size for these barrel lengths with middy tubes?

I want to be able to shoot M855 and match grade ammo. Will shooting M855 wear the barrel out or degrade it any more then match ammo?

This will be used for CQB to 300 yards but with hopes of going to 600 occasionally.

Any thoughts/ help would be greatly appreciated.

Also if you know any qualified smiths that can do this job?


Full Member
Apr 8, 2009
Re: @ AR15 and barrel experts. Barrel question?

Keep it at 18" or trade it for what you want. Trading will save money in the long run.

Heat kills the barrel faster then anything else except cleaning a barrel. Should say cleaning with the wrong stuff and to much.

Gas port would have to be opened up. How much depends on length.

An 18" Lother Walther is a really nice stick.

Using M855 in the Wylde chamber? Not me, one possible danger is that it generates more pressure in the chamber.

Who can do it fast and right? ADCO.


Full Member
Feb 14, 2008
North West Arkansas
Re: @ AR15 and barrel experts. Barrel question?

Cut and crown and try it with the current port size and see not a big deal if it ends up needing opened up.


Full Member
Nov 11, 2011
Re: @ AR15 and barrel experts. Barrel question?

Be aware that if you drill it to open it up, and odds are good that you will at 14.5''- you will most likely leave a burr and will need to DEburr it, elsewise the burr will get strung down the bore and if it overlaps a land, could cause accuracy issues.
Were it a run of the mill barrel, it would be less of a concern, but you are dropping some money for a really nice barrel and you don't want to take chances do anything that might screw things up.
I have drilled gas ports and stepped up the hole to minimize the burr and as well used super sharp bits to assist in NOT burring more than necessary. Proceed with caution and care- if you have to drill.