3 Point Jam

I was just about to experience the first jam-free sequence of 400 rounds cycled through my 3” Kimber 1911 in .45ACP… then I got a 3-pt jam. Bummer. The good news, I hope, is that the 3-pt jam is not what has plagued this pistol over the previous 2,500-ish rounds. The first persistent failure mode I had was failure to reach battery - which typically happened with a full magazine. I solved that by polishing wear surfaces and shooting the gun. I also swapped out the recoil spring for the stiffer version, which I think helps force the slide & cartridge into full battery. The next failure mode, which may have contributed to the FTRB, was that the slide stop pin was too long and rounds would hit the pin during the feeding cycle, which would cause the slide to lock back as if the magazine was empty. I solved that by very, very slowly removing material from the slide stop pin. I did swap the Magazine out once, but that made both problems worse.
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So now I got this disappointing jam. Most of the stuff I read online regarding 3-pt jams pertains to something in the gun being out of spec, which I don’t think applies here given the number of cycles without a 3-pt jam. I’m shooting three boolits right now - a clone of the H&G #34 (230 gr RN), loaded to 1.275” OACL; the RCBS clone of H&G #68 (200 gr SWC), loaded to 1.235” OACL; and a Saeco 230 gr TC boolit loaded to 1.190” OACL. The Saeco boolit is the one that jammed and that mold is pretty new to me. Most of my shooting is with the 230 gr RN boolit. I think the jam was caused by the short cartridge length. The offending round was loaded with the starting charge of 5.0 gr of W231.
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I guess I have to start over again, except without the Saeco boolit. I’ll load up 250 rounds of the SWC with a light charge of W231 and 250 rounds of the RN boolit with a stiff charge of True Blue (and a few more with Enforcer). Wish me luck on getting 500 rounds through without a hitch! If that succeeds, I’ll have a 2-c Saeco mold up for sale.
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Any advice is welcome.

What is the max the Saeco bullet can be in OAL and still chamber? Try going longer with that bullet if possible and try again. A three point is often caused by a low frame ramp strike which is OAL related and also based upon which round in the magazine (near first most common) is being fed.

My 3-pt jam was the last round of the magazine.
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I could go longer with this boolit. I would honestly prefer the heavy TC to go with the short barrel. A heavy bullet gives more time for the powder to burn, and the meplat is helpful where a hollow point won’t expand. I shot some Underwood Ammo +P rated rounds and got about 850 fps. I haven’t seen more than 775 in my handloads yet.

Last round is sometimes inertial misfeed. Does the follower have a dimple on it? Give longer OAL of 1.200-1.220” a try if possible.

Most 3-point jams are magazine spring related; weak springs will cause a lot of different feeding problems, try a new spring.

I shoot H&G 68 bullets at 1.250" OAL, this works in all my 1911's and worked in a 3" Colt I used to have.

In my bout of Weird Science with the 452423, I learned that while the 1911's feed pawl of course strikes the round to move it forward from the magazine, that same movement also makes the cartridge dip downward slightly at the nose, and how much it dips depends upon where it is in the magazine stack. We need a cartridge geometry that's going to get the nose of the round forward out of the magazine and onto the feed ramp before the nose-diving component can create an angle the pistol doesn't like - and it needs to do that whether it's the first round in the mag or the seventh.

Your cartridge overall length will be limited by two things: ability of the round to fit in the magazine, and keeping the first full-diameter driving band from binding up on the chamber throat or catching the inside of the slide stop lever. Within those limitations, load them as long as you can.