Patriot Ordnance Factory

[TMan]

www.pof-usa.com/main.htm

There is a video on this page that explains extraction in semi-auto rifle quite well. I never understood the "timing" that is involved.

["DoubleAction"]

More on The JP Adjustable Gas Systems

www.jprifles.com/1.4.6_gs.php

["DoubleAction"]

....JP Custom has an answer to problem of regulating the gas pressure on the AR-15 type rifles, for some time now.

AR-15/M16 ADJUSTABLE GAS BLOCK

www.brownells.com/.aspx/pid=7592/Product/AR_15_M16_ADJUSTABLE_GAS_BLOCK

Price:$69.99 - $119.99
Pressure Adjustable For Smoother Cycling
Replaces the factory front sight/gas block and allows you to tune the gas system for smoother cycling and operation. Especially critical on match and varmint rifles when shooting both factory and custom-loaded ammunition. Simple setscrew lets you control the gas flow, so you can customize the setting for each load. Hex head setscrews clamp the block securely to the barrel. Installation instructions included. Standard model features a topside Picatinny rail for mounting flip-up front sights and other accessories. Available in lightweight aluminum or stainless steel for additional muzzle weight. Fits barrels with .750" O.D. at gas block. Heavy - Aluminum, with rail, fits heavy barrels with .936" O.D. Low Profile model fits under handguard on .750" barrels. Rugged, all-steel construction resists gas erosion and helps maintain rifle’s weight distribution. A2-Style – Retains the classic look of military rifles and carbines. Two side-mount hex head screws clamp the block securely to barrels with .750" O.D. at the gas block position. Rugged, stainless steel construction resists gas erosion and helps maintain rifle’s weight distribution. Hard, abrasion-resistant black oxide finish.

www.jprifles.com/3.2.php

.....Take notice to the JP muzzle brake on the AR Rifle, on the right. I first saw the JP muzzle brake on one of rifles, used by one of Colt Team members in competition and Colt used it in their catalog.

More on The JP Adjustable Gas Systems

www.jprifles.com/1.4.6_gs.php

["DoubleAction"]

....With Pistols,;The shorter the barrel length, the heavier is the recoil spring.

....If one was to exceed the limits of the standard barrel length of a 1911, which is 5 " inches, you might be faced with problems with the longer slides. The Six inch AMT Hardballer slides & barrels had this problem, about the recoil springs not having enough power to cycle the slide on certain .45 acp cartridges.

....The feed ramp might have a lot to do with the feed, rather than the recoil spring, as it did with my Sig Sauers, with their ramp barrels.

Feeding Problems: Flat Nose .40 S&W & Sigs
Thread Started on Jan 18, 2007

handgunforum.proboards.com/index.cgi?board=problems&action=display&thread=3114

I first mentioned having feeding problems with the flat nose fmj .40 S&W with the Sig Sauers. This problem was echoed by others I know, of which I've also seen at the range. Chuck Taylor mentioned this problem in an article he wrote several years ago but he blamed it on the magazine. I examined the flat nose .40 S&W bullet's path into the fully supported chamber of the Sig Sauer and found the bullet binding at the top of the chamber as it was being fed.

I've seen this occur in the P-229 and the P-226. I've also seen binding issues with my P-220 in 38 Super. I attempted to correct the problem by lightly polishing the bottom edge of the chamber and the ramp to smooth the feeding. I avoiding removing any metal, but rather to smooth the feed of the .40 S&W bullet in it's very tight chamber.

Taking the P-226 to the range, after having smoothing ithe feed ramp, I experienced no feeding malfunctions through 100 rds of Winchester and Aquila flat nose fmj bullets. These two cartridges were the ones which we found to be notorious for feeding malfunctions in the Sig Sauers. After 200 rds. the ramp was still very clean, which led me to believe the polishing also reduced the accumulation of fouling.