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10mm Ammuntion => Reloading 10mm ammo => Topic started by: Ten2six on March 31 2017 06:23:05 PM MDT

Title: Grand Power brass
Post by: Ten2six on March 31 2017 06:23:05 PM MDT
Is anyone else experiencing slightly higher than average case failures when shot through their GP? I had one break in half today leaving the end in the chamber thus ramming the next round in the end of it. I had one heck of a time getting the slide to let go.

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Title: Re: Grand Power brass
Post by: The_Shadow on March 31 2017 06:32:40 PM MDT
Well what is the ammo that you are using?
Am I seeing primers missing?
Is that a bullet that pushed inside one of the casings?

Need more info
Title: Re: Grand Power brass
Post by: Ten2six on March 31 2017 07:16:39 PM MDT
Sorry for the lack of details, I was having trouble loading pictures and got tired of re-writing the content every time. Sometimes I am a little tech challenged.

There are two Starline and two Sig cases there. Both have been loaded below maximum loads probably three times at the most. One case broke in the chamber as the extractor was pulling it out. Then another round was jammed in behind the half that was left in the chamber. I am thinking the rotating of the barrel during extraction adds stress to the case that was not there before.
And... there are two that have been resized thus the lack of primers.
Title: Re: Grand Power brass
Post by: The_Shadow on March 31 2017 07:50:37 PM MDT
The Cracks appear that they are still expanded out to the chamber walls and ejection is occurring and the rotation of the barrel is causing the crack to run around instead of straight accross.

What is the load data for these?  The powder maybe too fast burning snapping the cases as the expand to fill the chamber.
Title: Re: Grand Power brass
Post by: Ten2six on March 31 2017 08:02:42 PM MDT
Two were 9.6 gr. of Power Pistol behind a 165 gr. fmj. The other two I can't be sure, I didn't notice them until i was re-sizing.
Title: Re: Grand Power brass
Post by: The_Shadow on March 31 2017 08:25:15 PM MDT
Power Pistol is a great powder, but it does expand the casing to fill the chamber faster than Blue Dot or LongShot or AA#9

Have you tried to tune with an extra power recoil spring?  That may help some.
Title: Re: Grand Power brass
Post by: Ten2six on March 31 2017 08:59:22 PM MDT
I was using the stronger silver spring today, previously I was using the smaller red spring. I have had good luck with blue dot, I will work up some loads for the GP and see what happens. Of course I just stocked up on 2 pounds of power pistol last weekend!
Thanks for your input.
Title: Re: Grand Power brass
Post by: The_Shadow on March 31 2017 09:24:19 PM MDT
Try reducing the Power Pistol 0.2 grains...may help out.
Blue Dot has always been great for many of my loadings

Good luck and best regards! :D
Title: Re: Grand Power brass
Post by: The Earl o Sammich on April 01 2017 01:47:17 PM MDT
Interesting.  You say re-loaded maybe three times.  Were they all previously fired through the GP?
Title: Re: Grand Power brass
Post by: Ten2six on April 01 2017 06:16:51 PM MDT
Quote from: The Earl o Sammich on April 01 2017 01:47:17 PM MDT
Interesting.  You say re-loaded maybe three times.  Were they all previously fired through the GP?

Can't be sure on that as I almost always take them all out when I go. The odds are pretty good though as I have been working on breaking in the GP the mostly.
Title: Re: Grand Power brass
Post by: The_Shadow on April 01 2017 07:09:23 PM MDT
One other thing comes to mind is the chamber and is it smooth inside or have machining marks.
You might can take a casing drill out the primer pocket put a small bolt through it, chock it in a variable speed drill, coat it with some oil and very fine valve grinding compound to polish.  Finish up with dremel with soft fiber round cone and Flitz polish.
Title: Re: Grand Power brass
Post by: Intercooler on April 01 2017 07:13:37 PM MDT
Funky looking line in the brass huh? I would think the barrel line would be a perfect circle further back?
Title: Re: Grand Power brass
Post by: Ten2six on April 01 2017 08:34:57 PM MDT
I can definitely tell which cases were fired though the GP cracked or not!
Title: Re: Grand Power brass
Post by: Ten2six on April 25 2017 08:05:29 PM MDT
Well...this happened again today so I inspected the chamber and it wasn't to bad but I polished it with my dremel and some rouge, it's not mirror finished but hopefully it'll help!
Title: Re: Grand Power brass
Post by: PCFlorida on May 04 2017 06:38:37 PM MDT
Quote from: Ten2six on April 25 2017 08:05:29 PM MDT
Well...this happened again today so I inspected the chamber and it wasn't to bad but I polished it with my dremel and some rouge, it's not mirror finished but hopefully it'll help!

Have you had an opportunity to try it yet?
Title: Re: Grand Power brass
Post by: Ten2six on May 04 2017 07:51:22 PM MDT
Sorta, I ran 150 rounds through it with no breakage but the brass had never seen the GP before. I hope to get out again this weekend after I pick up my latest addition ( S&W 1006). I will report back asap!
Title: Re: Grand Power brass
Post by: PCFlorida on May 04 2017 08:09:02 PM MDT
Cool, enjoy the new toy!
Title: Re: Grand Power brass
Post by: Ten2six on May 04 2017 08:13:44 PM MDT
Thanks!...I am sure I will!