Ramp & Throat Job/To Tuner

[combatantr2]

Tuner;

Seen your no. 2 pic on what you said of an example of a barrel overhang, but honestly I could not see any negative difference on my box stock norinco 1911/45acp. My box stock norc seems to have (at least based on the pic you posted) the same degree of barrel angle to feed ramp contact with your posted pic, and yet I have not encountered FTFs or failure to return to battery, or stem bind problem as you have mentioned. My barrel or chamber contact to feed ramp is zero to zero, at least in my view. So what gives?

Thanks and I would appreciate your kind reply.

A side question on 1911 feed ramps on steel frames - by continued shooting thousands of rounds 'say 30 to 50thousand rounds, is it possible that feed ramp angles can be change due to the continued hammering of live rounds during feeding against the feed ramp? Specifically on Norinco steel.

 

[1911Tuner]

Norinco

Every Norinco that I've seen has had the lower edge of the barrel ramp flush with the top of the feed ramp, and most have fed very well...probably at least partly due to the fact that the barrel ramps have been cut so deep into the chamber that the case head support is a bit compromised, but also in part because the feed ramps have been well within spec at 31 degrees....AND
the breechface angles have been right. The few that I've checked that were
right on the peg or slightly out of spec in regards to these two critical angles haven't been right...and the guns weren't very feed reliable.

Fairly easy to compensate for by setting the bottom of the barrel ramp forward a little and recontouring the ramp...but the hard chroming presents a
problem in having to grind through it, and...once breached...sometimes has the tendency to flake or peel.

The Norinco's barrel positioning relative to the feed ramp appears to come from the lower barrel lug location being too far forward, and once a good barrel is installed, the issue disappears with the lower edge of the barrel ramp locating well forward of the feed ramp...and usually more than the 32nd inch minimum.

I like the Norincos, and own 10 of the things. The barrels are the weak link, without question. Springfield's stainless one-piece service barrels provided a pretty good match, and a near drop-in fit...but I hear that the company won't sell those separately any more. The next step is the Kart Easy-Fit if the frame and slide specs allow for full vertical engagement...and some require peening/swaging of the frame rails, and lowering the slide...in addition to a full gunsmith fit barrel to get optimum upper lug engagement. Every Norinco slide that I've been involved with has the second lug wall located slightly too far rearward, which requires light fitting of the second barrel lug
to allow equalizing all three lugs. This can vary from as little as .002 inch to as much as .005 or sometimes more. Every so often, you'll also run into one that locates the slide's #3 lug wall too far forward, which means that equal bearing on lugs 1 and 2 are likely the best you'll get without a lot of extra, tedious work. As long as you have full vertical engagement, 1 and 2 will do.