with a 200 grain bullet? I made some loads today with 7.1 grain Power Pistol. The slide cycled fine but I did have it not want to feed the first round when I released the slide release. A little bump on the back of the slide and it went into battery. Then all rounds fed fine. I had the oal set to 1.26 or reasonably close. Also I think my crimp was around .423 - .424. I could probably crimp a little more, but they pass the case gauge and since they are cast bullets I don't want to crimp too much. Any help you can give will be appreciated.
Max load with Power Pistol in 200 grain is 7.6 grain at 1.260". At 7.1 grains you could safely load a bit shorter.
I have feed issues in one of my guns if I load longer than 1.250" with some bullet profiles. As a result I just load everything about 1.245"-1.250".
Does your rounds pass a Cartridge Case Gauge as put together? If yes you may need a shorter COL to adjust the tipping angle because of the wide flat nose (Meplat over 0.25) Double Tap adjusted his large Meplat WFN to 1.2420" COL to help feeding.
If NO! then you need to look at the entire case length to study if the case is too large in diameter. Pass through sizing can help with ironing out most issues. However if you are using 0.4020"cast bullet it might not pass the case gauge.
Do you seat and crimp in separate steps? Sometimes seating and crimping in the same step can roll up lead ahead of the case mouth or even roll inside the case. I try for 0.4215" - 0.4220" on the jacket bullets and 0.4220" - 0.4225" on most of my cast bullets.
Yes the rounds pass the case gauge. I may trying to go just a wee bit shorter and see what happens as it sounds like I can go shorter. Would like to stay with that bullet as it works quite well for me in my STI for making major in USPSA for 40 S & W. It doesn't have a real wide nose. I can also crimp slightly more and see if that makes a difference. I will be the first to say that I am not the best at using the calipers to measure. One time it will read one thing and the next time something different.
I just measured some factory 180 grain fmj I had here (2 different brands) and they were much shorter than 1.260, less than 1.250, so it looks like I should go just a little shorter and try that. I will probably go down to 1.258 or so and try that and then go a little shorter if I need to. Thanks for the information.
The SAMMI spec is 1.240min and 1.250 max. Here's the data sheet http://www.saami.org/PubResources/CC_Drawings/Pistol/10mm%20Automatic.pdf (http://www.saami.org/PubResources/CC_Drawings/Pistol/10mm%20Automatic.pdf)
blfuller, you are correct with the SAAMI specs. These are guidelines providing a range where things should work with most all firearms and bullet choices for 10mm.
However some bullets because of their nose profile or meplat can affect the feeding angles as the cartridge starts to tip over into the chamber, even though they fit the magazine, they pass the cartridge case gauge, etc. This is what maybe the issue that bigarm was having...
In order to change that tipping angle bigarm can reduce the COL as I mentioned previously.
The following was shown at the 38Supernet http://38super.net/index.html (http://38super.net/index.html) which hass a ton of info that can also be related to the 10mm cartridge. http://38super.net/Pages/Bullet%20Design%20and%20Feeding%20Reliability.html (http://38super.net/Pages/Bullet%20Design%20and%20Feeding%20Reliability.html)
http://38super.net/Pages/Overall%20Length.html (http://38super.net/Pages/Overall%20Length.html)
(http://38super.net/Smart%20Figures/DimensionsRoundFlat.gif)
(http://38super.net/Images/timing.jpg)
Interesting on oal as my Lyman manual says 1.260. Maybe I should check that again as I could have misread it. At any rate, I will shorten them and try it.
That graphic is very interesting.
Thanks
When you get a chance click on the links and read about it in more details. It is very interesting!
I shortened to 1.255 and am still having the same problem on just the first round out of the magazine. It looks like the picture in the article. Incidentally I just read the entire article. Very interesting. I am going back out to the shop and try 1.250 and see what happens. The bullets also seem to be shooting low.
Tried 1.250 which seemed to solve the problem of the first round not wanting to load. Then upped to 7.3 grains as 7.1 and then 7.2 were shooting very low. Still a little low, but much better. Made up a hundred rounds to try. Hopefully will get a decent day weather wise soon and I will chrono the load and see what velocity I am getting.
Glad you found some improvements at the 1.2500" (I load most all of mine at that length but they don't have a large Meplat), this is what makes handloading so much fun!
Another thing and you may already be doing this is to tap the magazine as loaded to set the cartridges fully to the rear of the magazine...tap the rear edge against the palm or leg.
As mentioned some of the larger Meplat bullets may require an even shorter COL, just like DT is doing @ 1.2420"
I will try these out and see how it goes. I did find that I had to make sure the rounds were way back against the back of the magazine. Have never had to watch that close with 45 acp or 40. It's something I will keep an eye on. If I have any more problems I will go a little shorter, but I ran several magazines through when changing the amount of powder and all worked.
Loaded some at 1.245-1.246 and chronographed both loads.
OAL 1.250
average velocity 1143
extreme spread 32
standard deviation 16
OAL 1.245-1.246
average velocity 1139
extreme spread 61
standard deviation 16
power factor on shorter load is 227!
Are these too hot for a Delta Elite or okay? When I tried 7.1 and 7.2 grains they seemed to shoot low, but maybe I was pulling them. Of course I could try CFE or 231 or True Blue also. May even have a pound of Unique.
They seemed a little snappy but certainly controllable, not terrible.
What do you think?
Quote from: bigarm on April 01 2015 09:36:59 AM MDT
Interesting on oal as my Lyman manual says 1.260. Maybe I should check that again as I could have misread it. At any rate, I will shorten them and try it.
That graphic is very interesting.
Thanks
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If you look closely at the SAMI diagram the max is 1.260 it is just a little fuzzy I had to get the magnifying glass out and double check because all of the books I have (10 of them) have 1.260 as max COAL and I make most all of my 10 mm hand loads COAL at 1.258 so I had to check to make sure. Load safe and use what works best in your firearm.
I load to 1.250" pretty much all the time, not sure why but I do.