Louder bang, double ejection

[foggyandcold]

Shooting a 45acp 1911 (les baer) with reloads (185gr SWC with 3.8gr WST). I'm new to reloading so whether this is a reloading issue or something else, I appreciate all insight.

Loading 5 rounds per magazine because I'm shooting a practice bullseye (precision pistol) target. On the 4th round of the second magazine, the 'bang' seemed a fair bit louder, the recoil a bit stronger, and both the spent case (4th) and also the last (live) round were both ejected. The 5th round flew up and forward, over the firing line table and landed a few feet in front to the left a little.

I'm perplexed by this.. any thoughts on how that can happen?

The pistol has a lower-strength recoil spring in it; 11lbs IIRC. I've probably put ~50 rounds thru it with this spring - so, not a lot. I have a few higher-strength ones and will test out what the strongest one is that still cycles the pistol reliably, I just haven't gotten to that yet (today's session was the first time with an optic to zero). I also haven't figured out what projectile and load are most accurate in this pistol, so, plenty of work to do.

Perhaps there are two distinct issues that combined together -- first, a too-light recoil spring that could stand to be a bit stiffer, and second, maybe one projectile was somehow seated a little deeper or something? I'm using a Dillion 550B. I am not sure what I could have done to make a round that has a bit bigger bang/recoil. Certainly a double-charge is a bigger bang but based on peoples' descriptions of those, they are a huge problem, not +20% recoil? So I'm wondering if seating depth or crimp tightness could somehow have varied. These were all S&B brass; the first reload of them.

Thanks in advance for any help. Lots to learn

[ar15barrels]

Something to look into is bullet holding tension.
If the bullets are not a tight enough fit in the brass, the bullets can possibly be getting seated deeper from recoil while shooting the pistol.
A way to check for this is to measure the OAL of the 1st round you load into a magazine followed by 4-7 more and then shoot all but the last round and re-check the OAL of that round to see if the bullet is getting seated deeper.

Short of a problem like that which would be related to either sizing die or case expander dimensions, the next possibility is that you had an uneven powder charge with more powder in a specific round.
That happens when you stop and work on the press and then start loading again.
The powder sitting in the powder measure settles with each cycle of the press so if you cycle the press several times without throwing a charge, you will get a high charge for that first drop after several press cycles.
Dump a few charges to settle in the powder measure after stopping and working on the press before you continue loading.

[foggyandcold]

Amazing -- thank you. I can check the first suggestion and then be very careful about the second. Neither one of them being at issue would be too surprising. I do have the last (5th) round that ejected forward and will measure it later. Since it went flying and who knows what orientation it landed in (perhaps smack on the nose which could have seated the bullet further?), I won't be sure that a shorter OAL is necessarily due to recoil-induced seating, but it'll be a little extra information anyway.

I have to say -- the list of small potential "gotchas" is not short.

I'm delighted to be reloading. And Randall your stickied posts from many years ago, and continued posts and contributions of knowledge, have been part of what gave me reasonable confidence that this is doable without too huge a risk of messing things up. So a big thank-you. I'd love to be a private pilot but have concluded my life circumstances (two young kids) and availability of time/attention are *not* compatible with being safe 99.9999% of the time (or whatever the safety rate of general aviation is)... so that's something that's not (perhaps not yet, or perhaps never will be) part of my life. But reloading is very satisfying, as is trying to raise my skill level when shooting bullseye.

[Revoman]

To add something minor to AR15Barrels excellent comments.
You can also check bullet setback by measuring overall length after loading.
Then simply press the now live round, bullet end to the side of a wooden bench top for instance and remeasure the overall length.
If it's shorter, then more case friction is needed.
You'll need to press fairly hard; I use my thumb (you don't want to press with anything hard enough to set off the primer of course!) and push using my body weight on my thumb to provide good pressure simulating a degree of recoil. It's usually enough to know that it's good to go, or not.
Once you do a few and are loading the same brand of brass (important due to brass wall thickness) you won't need to do every round, as you have adjusted the die to do its job correctly.
Then prove it out using AR's method at the shooting range.

mike