200 grain WFN wont plunk in the KKM loaded at 1.250 ... they will at 1.240.
I want to make sure this is a safe practice before I load a few. I see some threads here that indicate WFN need a shorter OAL?
Thanks much ...
PsTaN
Reduce 10% and work up.
I have a 6 inch KKM on my G40 and I seat the Montana Bullet Works 200 grain WFN to 1.240 to get reliable feeding and to work properly in my magazines. I use this same seating depth or COAL for all my 10mms using 200 grain WFN boolits. I use a COAL of 1.250 for 200 grain Hornady XTPs and that length chambers and feeds just fine in all my 10mms. SAAMI COAL is listed as 1.240-1.260. So, if you do as sqbullet stated, you'll be just fine with the KKM.
You didn't ask but I'll share some experience I have with the 200 grain WFN boolits. In my preliminary load development, Longshot gave me the highest velocity while Blue Dot gave me the best accuracy. I have a pound of AA#9 I haven't tried yet and it might work well too.
Yes some of the WFN designs need shorter COL especially the ones with the total flat designs, the ones with a slightly rounded edge can usually go longer. However even at 1.2500" they should pass the Plunk Test. It is their feeding angle that usually causes issues. The WFN tends to hit the top of the chamber at an angle, adding extra drag as the case head tries to slide up the breech face during cycling.
When you are plunk testing and they don't fully chamber, you need to visually check to see if the casing edge has bullet material rolled over its edge. The edge has to be free and clean if not it can hang up on the end of the chamber cut.
Also be sure that the bullet didn't squeeze to a larger diameter due to crimping action. If the bullet is too large it can hang up on the end of the chamber cut.
I doubt that a properly seated bullet even at 1.2600" even with the WFN would hang up on the trueing cone or rifling. If that were the case you would see markings on the bullet nose or ogive.
The other reason for failure to fully enter a tight chamber is reused reloaded brass that haven't been pass through sized. The 10mm, 40S&W are straight wall casings, as such they can experience case swelling below where the normal sizing dies can't reach because of their radiused opening and the shell holder or shell plate occupying that space. They will stick in the tighter chamber at the rear above the start of the extractor cut.
The bullets I ordered are from Double Tap. I'm sure some of you know a better source. The powders I have on hand are Unique and Power Pistol. I'm looking for a load at 1000fps.
Suggestions?
And thanks so much for the help. I'm still learning how to load 10mm.
P
Power Pistol will get you there easily... 8.0 grains will do about 1180 fps
Yep. Handloads.com has the older alliant data for power pistol online. 6.9 grains start, with 7.7 grains max giving 1145 fps with a 200 grain FMJ at 1.260.
You WFN is going to be a fair bit shorter than an FMJ, both due to the lack of a less dense jacket and due to additional weight in the nose. Should be pretty close to the same internal capacity when you seat to 1.240".
Lead is gonna seal the bore better, so with less blow by you will make pressure sooner. I would bet that starting load of 6.9 grains may be over 1000 fps.
Good luck!
Also make sure they are not sized too large diameter it will exceed the diameter in the case ?
Sizing is correct ... was all a matter of being loaded too long from what I now know. I'm going to start the ladder at 7.0 grains of PP and work from there.
I know my way around 44 Mag and can do what I need with it ... still learning 10mm.
Thanks to all!
P
Chrono and Function test today.
7.0 grains PP loaded at 1.240 COL yielded an average of 1075 fps. Function was perfect, brass looked excellent, and no leading.
Thanks to all.
I'll test for accuracy as soon as possible.