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View Full Version : Rx: New Century L1A1 Receiver Failure to Feed


larphred
June 21, 2002, 13:38
Built two identical Aussie L1A1s on the new Century inch receivers. The receivers have taken a lot of work (spelled "fun"), but there's enjoyment in the challenge. The last (I hope) problem has been the inability of the bolt to strip a round from the right side of the magazine and guide it into the chamber. One one of the guns, I dremel polished the feed ramp (I use the term feed ramp loosely here) as much as possible. On the other gun I really Mickey Moused (or professor coyote'd for those who prefer) the feed ramp. The breech face poses a flat obstruction to the progress of the tip of the bullet into the chamber. So I kneaded a small wad of QUIKSTEEL (epoxy putty) and pressed it into the barrel/receiver junction where the obstruction is located, allowed 24 hour curing time, then finished off with a round file. Took both to range yesterday and fired 60-80 rounds from each rifle. The polished feed ramp rifle functioned about 85-90% of the time where the epoxied rifle fed 100% of the time. I kinda imagine the epoxy won't hold up forever, but I'll test it for as long as it works.

W.E.G.
June 21, 2002, 15:01
So, the magazine engages TOO LOW relative to the axis of the CENTURY receiver threads?

Can you rock the carrier a lot when it rides in the grooves? I wonder how much higher the bolt carrier sits when the bolt is installed as compared to when the bolt is not installed? Run same test with and without magazine installed. Tall grooves in the receiver allow the carrier to run in different planes during actual cycling? Tall grooves allow the carrier to run canted (causing the non-loaded side of the carrier to override one side of the magazine)?

:rolleyes:


...and on the eighth day he created IMBEL.

I think I'm starting to see why DSA feels their drastically higher prices may be justified. Consistency. The cheap stuff (except IMBEL) is such a crap-shoot.

larphred
June 23, 2002, 18:03
Gary--yes the carrier has both lateral and vertical play. I compared with my Imbel guns and it may be slightly more in the Century than the Imbels. I would think a sloppy carrier/bolt complex might just over-ride the round instead of jamming it into the breech face. Careful inspection of Century vs. Imbel feed ramps shows significant differences. Angle of ramp seems more gradual on Imbel....steeper on Century. Also Imbel has double scallops on ramp...one to feed from right and one to feed from left, where Century has a single radius. I'm thinkin' the feeding problems are probably feed ramp geometry.