And people laughed at me when I started loading RMR FN bullets in preference to the more traditional RN
This thread was meant for progressive presses where resizing operation may affect bullet seating operation.
He's just pulling your chain for doubling up.I can't say I've heard of "pre-resizing" Does one resize before resizing?
No, just resizing in separate step.
The shellplate tilt/deflection affecting OAL variance is only applicable to progressive press using shellplate.Nope it was a serious question.
I don't use a progressive press ... I'm using a Co-Ax and I "batch load"
I hear your comments about "stacked tolerances", and I can see where you are going, but the other variations that go into the stacked tolerances are there for *both* techniques, which means to me, they become a constant across both equations.
Your points are very valid.I am not saying that this COAL difference does not add or detract to the shown accuracy, but I am not sure it is worth the extra effort ... of pre-resizing the brass
I believe many would agree that bullet (or rather projectile) is the single most important component of accuracy. But testing of projectiles cannot commence until I have other reloading variables standardized (headstamp, OAL, powder, primer).In fact, I would further postulate that manufacturing tolerances in bullet manufacturing could account for part of the differences shown
Thanks for all of the effort you put into your Mythbuster threads! We all love them and they make us think!!!
Hopefully they provide more thought provoking stimuli to produce more accurate loads instead of debates about color of press.Yes. Thanks for these mythbuster threads. I learn from them.
Since not all the reloaders lube their pistol brass, I wasn't going to include lube testing. However, I did pick up a can of One Shot to test whether residual lube inside case neck will affect neck tension/bullet setback. I am figuring out a "standardized" method to evenly apply lube inside the case neck for testing.But what about lubing the cases. That puts less stress/flex in much the same way does it not? Would that not be equivalent to pre-resizing? What if one did both?? AAHH, where does it end?
OK. Test was done with RMR 124 gr FMJ FP bullets.
Test procedure:
- BLAZER 9mm brass were resized and they ranged from .749" to .752".
- Five cases measuring .750" were selected
- Rocky Mountain Reloading In-House 124 gr FMJ FP
- Test rounds were loaded on Pro 1000 using Lee dies
- Frankford Arsenal dial calipers verified with Vermont pin gages
Regular Reloading - Bullets were seated with all 3 stations full. OAL/COL sorted from shortest to longest:
- 1.070"
- 1.070"
- 1.071"
- 1.071"
- 1.072"
Pre-Resized Brass Reloading - Resizing/depriming die removed from Station 1. All bullets were seated while flaring a case in Station 2. OAL/COL sorted from shortest to longest:
- 1.069"
- 1.069"
- 1.070"
- 1.070"
- 1.070"
Summary - Using same BLAZER headstamp brass produced .002" OAL variance while using pre-resized brass produced 001" OAL variance
Don't you love how my suggestions always involve MORE WORK on your part!!!But what about lubing the cases.
Ask and you shall receive.I did pick up a can of One Shot to test whether residual lube inside case neck will affect neck tension/bullet setback.