Do cast bullets "rebound" after sizing.
- Thread starter Rockydoc
- Start date
Ian
Notorious member
Bugs Bunny running around in the margins and popping out of the sprocket holes munching a carrot is for sure distracting, I concur. But what else ya gonna think about on an hour drive to work?
Bret4207
At the casting bench in the sky. RIP Bret.
Mad, oh man! I read every word and laughed all the way through it. Good humor lets us make fun of ourselves. I don't know when Mad changed, but I looked at a copy some years back and it was just stupid. Thought it was just me so I looked at an old copy, still funny. I dunno!
Car-toons was a good one too. Funny car related stuff. All clean humor too.
Car-toons was a good one too. Funny car related stuff. All clean humor too.
CWLONGSHOT
Well-Known Member
Intresting thing happened...
So last week I cast up about 13# of three different bullets all same alloy but different powdercoats. All handled exactly same. No wuench from mold. Powder coated and quenched after PC. Size within hours.
First was RCBS 45-300 swc I GC these after Eastwood FLB PC and sized to .454.
Second was MP 357-165 MIX deep HP & Penta HP. PC with Specflacklular grey. Sized .359.
Last was Saeco 353 and PC with Columbia Coatings CHROMA CHROME. SIZED .359
I wrapped, bagged a d shrunk wrapped all and shipped to Indiana.
Last night my buddy called. He received box and made dummies cartridges for each bullet. (All new to him) the Saeco twice stuck in his seater die!! (Chroma Chrome)
Now I know this powder coats thickly .005/.006. Its as if it expands as I shake it down to what appears a thin coating. He mikes diameter and its .361! None if the other two bullets enlarged at all. But these chroma chrome surely did!! He ran them all twice tbru a .358 sizer and now all appear to be .359 and holding.
I have not experienced this. But I have t used this powder THAT much and know its thick coating.
CW
So last week I cast up about 13# of three different bullets all same alloy but different powdercoats. All handled exactly same. No wuench from mold. Powder coated and quenched after PC. Size within hours.
First was RCBS 45-300 swc I GC these after Eastwood FLB PC and sized to .454.
Second was MP 357-165 MIX deep HP & Penta HP. PC with Specflacklular grey. Sized .359.
Last was Saeco 353 and PC with Columbia Coatings CHROMA CHROME. SIZED .359
I wrapped, bagged a d shrunk wrapped all and shipped to Indiana.
Last night my buddy called. He received box and made dummies cartridges for each bullet. (All new to him) the Saeco twice stuck in his seater die!! (Chroma Chrome)
Now I know this powder coats thickly .005/.006. Its as if it expands as I shake it down to what appears a thin coating. He mikes diameter and its .361! None if the other two bullets enlarged at all. But these chroma chrome surely did!! He ran them all twice tbru a .358 sizer and now all appear to be .359 and holding.
I have not experienced this. But I have t used this powder THAT much and know its thick coating.
CW
Dimner
Named Man
I had an odd experience yesterday that reminded me of this thread. I had recently performed some testing with my Win 94 and M1 garand with a RD designed 310-178 grain bullet. I had covid a couple of weeks ago and felt like junk, so I just powder coated bullets and reloaded for almost 6 days straight.
For the M1, I sized the bullets to 0.309 before and after PC. They were water dropped out of the oven. The brass was freshly annealed and sized, then mouth expanded to 0.306.
For the win 94, I sized to 0.311 before and after PC, as the 94 has an oddly large groove size between 0.3095 and 0.310. The bullets were air cooled out of the oven and seated in brass freshly annealed and sized, then mouth expanded to 0.308.
Anyway, I loaded these bullets about a week and a half prior to the actual range trip. Then did my test earlier this week, Tuesday and pulled the unshot bullets last night. The bullets were extremely difficult to pull using my RCBS collet bullet pull setup. Like grumpy, sailor cursing hard. I was surprised how difficult these were to pull. I measure the pulled bullets and they were 0.001 to 0.0015 larger at the driving bands than when I loaded them. I cannot attest if the brass had any spring back at the mouth that could have added to the experience. The difficulty of pulling the bullets was nearly the same for
Caveat: This was my first time pulling Powder Coated bullets with a Tumble Lube design. Who knows maybe that is what made them harder to pull. I guess there is a scenario where my other bullets I have pulled in the past have rebounded the same way, but I had not noticed any issues pulling them from the case.
Anyway, these bullets did seem to rebound for some reason. I guess, I'll have to start keeping notes on this and see if I can find a trend.
For the M1, I sized the bullets to 0.309 before and after PC. They were water dropped out of the oven. The brass was freshly annealed and sized, then mouth expanded to 0.306.
For the win 94, I sized to 0.311 before and after PC, as the 94 has an oddly large groove size between 0.3095 and 0.310. The bullets were air cooled out of the oven and seated in brass freshly annealed and sized, then mouth expanded to 0.308.
Anyway, I loaded these bullets about a week and a half prior to the actual range trip. Then did my test earlier this week, Tuesday and pulled the unshot bullets last night. The bullets were extremely difficult to pull using my RCBS collet bullet pull setup. Like grumpy, sailor cursing hard. I was surprised how difficult these were to pull. I measure the pulled bullets and they were 0.001 to 0.0015 larger at the driving bands than when I loaded them. I cannot attest if the brass had any spring back at the mouth that could have added to the experience. The difficulty of pulling the bullets was nearly the same for
Caveat: This was my first time pulling Powder Coated bullets with a Tumble Lube design. Who knows maybe that is what made them harder to pull. I guess there is a scenario where my other bullets I have pulled in the past have rebounded the same way, but I had not noticed any issues pulling them from the case.
Anyway, these bullets did seem to rebound for some reason. I guess, I'll have to start keeping notes on this and see if I can find a trend.
Dimner
Named Man
So, just to add some info back into this thread. In 2020 when the panic first was underway, I re-doubled my efforts to come up with a cast PC AR15 load. I ended up with a good load and a good bullet. Alloy is CWW+2% tin. Powder coated for 22 minutes then ice water quenched. My notes show that I was getting around 18bhn @ 4 days. 16 days @ 21 bhn. Seems these little buggers like to get hard.
But more importantly, I finished the project in late May of 2021. I then, cast maybe a 1500 - 2000 of these little guys. GC and PCed them all. Then after the 30 day period (actually July 3rd) I went through function testing. Basically groups using magazine feeding, 20 rounds. All fine. No failures to feed, no failures to eject. Removed my scope and installed iron sights and zeroed everything. End of project Mid July.
Fast forward to this summer and I decided I wanted to upgrade and use the same sets of iron sights on both my cast bullet AR and my jacketed full power load AR. This required me to do some rezero work on both ARs. Now my cast bullet AR loads from last year refuse to fully chamber. Not all, but maybe 1 in four will not chamber. Add onto that, the ones that do chamber, about one in 5 cannot be removed from the chamber without pulling a bullet (these are crimped loads)
I have no idea what's going on, but a some point in the past 13 months... these noses grew. Of course, now I have 700 of these loads on hand that I need to pull. I tried seating about 50 of them deeper, over half sheared lead and PC when seated deeper.
But more importantly, I finished the project in late May of 2021. I then, cast maybe a 1500 - 2000 of these little guys. GC and PCed them all. Then after the 30 day period (actually July 3rd) I went through function testing. Basically groups using magazine feeding, 20 rounds. All fine. No failures to feed, no failures to eject. Removed my scope and installed iron sights and zeroed everything. End of project Mid July.
Fast forward to this summer and I decided I wanted to upgrade and use the same sets of iron sights on both my cast bullet AR and my jacketed full power load AR. This required me to do some rezero work on both ARs. Now my cast bullet AR loads from last year refuse to fully chamber. Not all, but maybe 1 in four will not chamber. Add onto that, the ones that do chamber, about one in 5 cannot be removed from the chamber without pulling a bullet (these are crimped loads)
I have no idea what's going on, but a some point in the past 13 months... these noses grew. Of course, now I have 700 of these loads on hand that I need to pull. I tried seating about 50 of them deeper, over half sheared lead and PC when seated deeper.
Alloy with tin and/or antimony grows (over time) AND has 'spring-back' like brass. I re-worked my 401 Lee to drop 401 with my normal alloy ~ 3% Sb. I loaded some I cast with pure and just a tad of zinc added. Way undersized and tumbled real bad. Lesson learned. Use some recently cast, open up the sizer a SMALL amount, size a few, measure, repeat till where you want. WD alloy will have more springback than air cooled. Molecules in a solid do move around a bit.
RicinYakima
High Steppes of Eastern Washington
Oh yes! Ever look at a 200 year old piece of window glass? Ever wonder why the old churches had stain glass windows with lead strips in between? In a hundred years old painted glass will sag enough to ruin the art work.