LiveLife
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Reloads locking up the slide could be from:Hand loads. Loaded to spec, OAL 1.090 115 grain. Berry’s Plated
How would bad Ammo lock up a slide where it would move rearward but not completely retract.
- Case base not fully resized (if using unknown mixed range brass, culprit could be from 9mm Major brass)
- Case mouth flare not returned flat on bullet / not enough taper crimp
- Case neck bulge from deep seated/thicker case wall/tilted bullet
1. With your shell holder/plate in the uppermost position during resizing, if you see any daylight, adjust the dies so you don't to ensure you are fully resizing the brass down to case base. If you are using unknown mixed range brass, your problem could be from overly expanded (especially case base area where sizing die can't reach) brass loaded to 9mm Major power factor (Sadly, these unmarked brass are left on the ground by USPSA match shooters for unsuspecting reloaders to pick up to reload ... )
Now when I encounter increased resizing resistance with 9mm brass, I make sure the brass will readily fully chamber in my tightest barrel. If not, I will resize the brass again but if second resizing fails, brass is tossed for bulk recycling.
To check, drop your resized brass in the barrel. If they don't drop in freely with a "plonk", mark the brass with a marker and see where it rubs the chamber wall. If the rub mark is at the case base, it is from not full length sized brass and/or overly expanded brass.
2. This is less of an issue but still can contribute to slide not returning to full battery, especially due to reason #1 reloading on a progressive press. If shell holder/plate upward movement is limited (can see daylight between bottom of die and top of shell holder/plate) perhaps due to overly expanded case, case neck flare will not return back on the bullet and can prevent full chambering of the round.
To check, measure the case mouth of finished rounds. I usually add .022" to the diameter of bullet for taper crimp amount so for .356" sized Berry's plated bullets, I use .378" taper crimp. (For my various factory/aftermarket 9mm barrels, case mouth measurement larger than .378" will start to not fully chamber)
3. Over the decades, especially with non-domestic headstamp brass, I have noticed thicker and thicker case walls on 9mm brass. This has resulted in bulging of case neck especially about 0.200" below case mouth where case walls are thicker. You are using Berry's plated bullets which are typically sized larger at .356" (instead of more typical .355") and seating the bullet deeper at 1.090" (I am assuming RN?) will certainly cause bulging of case neck, especially with thicker case wall brass.
Check the headstamp of offending rounds and if they are the same, thicker case wall brass may be your problem. This thread/post lists case wall thickness by headstamp 0.200" below case mouth for your reference - https://www.thehighroad.org/index.p...d-bullet-setback.830072/page-3#post-107138221.
To check, drop your finished rounds in the barrel. If they don't drop in freely with a "plonk", mark the round with a marker and see where it rubs the chamber wall. If the rub mark is around the case neck, it is from bullet base bulging the case wall. If the bulge/rub mark is only on one side, it could be from tilted bullet during seating as bulge around the case neck should be uniform/even. If the bulge is uniform, you can try using longer OAL to see if the bulge decreases enought for you to fully chamber the round. If the bulging problem is only with a particular thick walled brass, sort out that brass. Another option is using smaller diameter (.355") sized bullets.
I hope this helps.
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