Don't Over Crimp But You Do Have To Crimp Enough

jtmckinney · February 22, 2013, 09:54 PM

My 40 cal semi auto pistol shoots factory loads (even the cheap stuff) with no problems but I have been having trouble getting the same reliability with my reloads. One FTF every magazine or two.

After cleaning my pistol and before re-assemblying with the barrel in one hand and cartridges in the other I compared the way factory and my reloads would feel riding up the feed ramp and into the chamber. There was a definate difference with my reloads having some resistance when they would break over and feed into the chamber.

I measured and looked but what I wound up doing is adjusting the crimp die down until the finished cartridge felt the same going into the chamber as the factory cartridges. 100 Rounds today and no FTF.

Just thought I would share.
Have a great day!
James

iraiam · February 23, 2013, 10:14 AM

sounds like there may have been a slight bell in the case mouth left from loading?

Glad you got it resolved, especially with the cost of .40 ammunition.

m&p45acp10+1 · February 23, 2013, 10:20 AM

Sounds good to me if they are working. Just remember to take a factory round, and run your finger nail over the bullet towards the base of the cartridge. You should feel a slight catch at the case mouth. Crimping for semi auto rounds is not crimping actually. You are just removing the flare, and ironing the case back straight. I do the thumb nail test on all of my semi auto reloads.

jtmckinney · February 23, 2013, 05:30 PM

Thanks for the replies!

I had tried several things with different COL's and powder charges. It is frustrating when cheap target ammo functions without fail and your reloads don't.

I have always tried not to overwork the brass at the mouth but in this case some extra work seems to be required.

Have a great day!
James

Brian Pfleuger · February 23, 2013, 05:38 PM

You might be able to reduce wear if you can cut back on the flare a bit. Same crimp, but if it's bent out less in the first place, less wear.

jtmckinney · February 23, 2013, 06:01 PM

I think I have gotten pretty good at putting the minimum amount of flare to get the bullet to start into the mouth but not too much to overwork the brass at the mouth.

What my post was really about was taking ammo that worked and comparing it to ammo that only worked 90% of the time and seeing how they fed into the barrel and that pointed me in the direction I needed to go.

Sometimes some good old fashioned tennasity is what is required.

Again, Thanks to all that replied!
James

February 22, 2013, 09:54 PM	#1
jtmckinney Senior Member Join Date: March 2, 2010 Location: Texas Posts: 490	Don't Over Crimp But You Do Have To Crimp Enough My 40 cal semi auto pistol shoots factory loads (even the cheap stuff) with no problems but I have been having trouble getting the same reliability with my reloads. One FTF every magazine or two. After cleaning my pistol and before re-assemblying with the barrel in one hand and cartridges in the other I compared the way factory and my reloads would feel riding up the feed ramp and into the chamber. There was a definate difference with my reloads having some resistance when they would break over and feed into the chamber. I measured and looked but what I wound up doing is adjusting the crimp die down until the finished cartridge felt the same going into the chamber as the factory cartridges. 100 Rounds today and no FTF. Just thought I would share. Have a great day! James __________________ “Government does few things well but it does them at great expense” Cal Thomas “When Government Can’t Be Trusted” 6/11/2013 When I am weaker than you, I ask you for freedom because that is according to your principles; When I am stronger than you, I take away your freedoms because that is according to my principles. Frank Herbert "Children of Dune"

February 23, 2013, 10:14 AM	#2
iraiam Senior Member Join Date: September 6, 2012 Location: Lakewood, CO Posts: 1,057	sounds like there may have been a slight bell in the case mouth left from loading? Glad you got it resolved, especially with the cost of .40 ammunition. __________________ NRA Lifetime Member Since 1999 "I ask, sir, what is the militia? It is the whole people except for a few public officials." George Mason

February 23, 2013, 10:20 AM	#3
m&p45acp10+1 Senior Member Join Date: May 3, 2009 Location: Central Texas Posts: 3,930	Sounds good to me if they are working. Just remember to take a factory round, and run your finger nail over the bullet towards the base of the cartridge. You should feel a slight catch at the case mouth. Crimping for semi auto rounds is not crimping actually. You are just removing the flare, and ironing the case back straight. I do the thumb nail test on all of my semi auto reloads. __________________ No matter how many times you do it and nothing happens it only takes something going wrong one time to kill you.

February 23, 2013, 05:30 PM	#4
jtmckinney Senior Member Join Date: March 2, 2010 Location: Texas Posts: 490	Thanks for the replies! I had tried several things with different COL's and powder charges. It is frustrating when cheap target ammo functions without fail and your reloads don't. I have always tried not to overwork the brass at the mouth but in this case some extra work seems to be required. Have a great day! James __________________ “Government does few things well but it does them at great expense” Cal Thomas “When Government Can’t Be Trusted” 6/11/2013 When I am weaker than you, I ask you for freedom because that is according to your principles; When I am stronger than you, I take away your freedoms because that is according to my principles. Frank Herbert "Children of Dune"

February 23, 2013, 05:38 PM	#5
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	You might be able to reduce wear if you can cut back on the flare a bit. Same crimp, but if it's bent out less in the first place, less wear. __________________ Nobody plans to screw up their lives... ...they just don't plan not to. -Andy Stanley

February 23, 2013, 06:01 PM	#6
jtmckinney Senior Member Join Date: March 2, 2010 Location: Texas Posts: 490	I think I have gotten pretty good at putting the minimum amount of flare to get the bullet to start into the mouth but not too much to overwork the brass at the mouth. What my post was really about was taking ammo that worked and comparing it to ammo that only worked 90% of the time and seeing how they fed into the barrel and that pointed me in the direction I needed to go. Sometimes some good old fashioned tennasity is what is required. Again, Thanks to all that replied! James __________________ “Government does few things well but it does them at great expense” Cal Thomas “When Government Can’t Be Trusted” 6/11/2013 When I am weaker than you, I ask you for freedom because that is according to your principles; When I am stronger than you, I take away your freedoms because that is according to my principles. Frank Herbert "Children of Dune"