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carstensxd45
11-09-2017, 11:05 PM
Am going from a 200 gr. bullet to a 230 gr. bullet in 45acp. want a round-nose bullet to replace my round-flat nose bullet. Since I "wildcatted" my powder charge, (Extra Lite shotgun powder from Alliant), there is no recipes in the books for it. If I am increasing the weight of the bullet (200 gr to 230 gr), how does that affect the powder? do I add more or take some away? I will be using a chrono to help me with the proper fps. Any help will be appreciated.

RobS
11-09-2017, 11:22 PM
Going up in weight likely means a longer boolit design. Logic would say to go down for a powder charge. Good Luck and be safe.

OS OK
11-09-2017, 11:52 PM
It seems that you pioneered this already back in 2014 with this video...

https://www.youtube.com/watch?v=pMGNYDJ_15I&feature=youtu.be&list=UUUiWTPURzNoccQU4prOc09A

based on Clays.

Why wouldn't you do the same again for the 230 grain...? There's only .3~.4'ths difference lower than the starting loads of the 200 grain.

carstensxd45
11-10-2017, 01:04 AM
was trying to save some time getting the loading right, btw, glad someone else watched my videos besides me

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runfiverun
11-10-2017, 01:37 AM
you'll drop it.
a full grain.

Kosh75287
11-10-2017, 11:02 AM
You don't mention what your charge weight was for the 200 gr. projectile, so coming up with one for a 230 gr. projectile isn't something I can do. In situations like this, I would likely calculate the new charge by inverse proportion. Let's SAY that the charge weight for 200gr. projectiles is 5.0 gr.:

(5.0gr. x 200gr.) = 4.4gr.
230gr.

If the charge so calculated still seems too heavy TO ME (without dedicated testing equipment how can we know?), I'll drop it 5% or 10% more. Since you are working with a chronograph, you should know about where you are, with one or two tries. The above formula is by no means fool-proof, but it usually gives me a tenable "best guess".

carstensxd45
11-10-2017, 02:05 PM
Boy, this is what I like about this forum, so many who are smarter than me and still willing to help. Thanks, am running 4.3 gr. of Extra Lite which gives me 890 fps. so according to the formula, approx. 3.74 gr. would give me about the same results. This at least gives me a starting point.

fredj338
11-10-2017, 04:31 PM
was trying to save some time getting the loading right, btw, glad someone else watched my videos besides me

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There are few safe short cuts to reloadding. If you move to a heavier bullet, powder charge should always go lower. So drop back to well below your 200gr starting load & work it back up, using a chrono, 1/10gr at a time.
BTW no real formula, every powder reacts diff as you get near max. So working up from minimum in 1/10gr increments, use the chrono. If you see a spike in vel or a flat spot, you are getting into pressure issues.

OS OK
11-10-2017, 04:38 PM
Using the 200 grain boolit...when your pressure ramped from 4.0 grains & 828 FPS to 4.1g. & 871 FPS it should have indicated to you that you were on the front ramp of a sudden pressure rise. That's a red flag.

Also you didn't chronogrph the 4.2g. and 4.3g. loads on video...What happened with those? I suspect you saw the rise even further!

Now you are going to start the 230g. @ the Max. load of your last test?

If it were me? . . . I'd hand my Mother in Law the shooting glasses, hold her beer and let her have a try at it!

Red Flag...

carstensxd45
11-10-2017, 10:07 PM
Fredj338, didn't know you were still around, you have been a real help in times past, glad to hear from you

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carstensxd45
11-10-2017, 10:12 PM
btw, OS OK, I did video the other powder weight, when I posted the video on YouTube, they cut the video back, I just didn't post the rest of the video

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carstensxd45
11-11-2017, 02:05 AM
hope I don't come across the wrong way, I do appreciate all the help

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trixter
11-14-2017, 02:28 PM
Going up in weight likely means a longer boolit design. Logic would say to go down for a powder charge. Good Luck and be safe.

This is the way I understand it too.