crimp functionality??

fedaykin · May 14, 2001, 02:37 PM

so, can anyone tell me how too much crimp can be bad and how too little crimp can be bad?
what does the proper crimp help do besides the obvious, headspace and bullet compaction on feed ramp.

how does it effect powder burn, pressure, cyling of the weapon.

i think i need to move to another powder

i am using wst with 5.1gr at 1.090 oal.
i am using a winchester fmj bullet.
i use a wolff spring at 15lb
if i have a full magazine i get a type 2 malf (failure to extract. i can see brass dings on the forward ejection port and the brass gets thrown forward at times.
this load chronos at 1180fps though.

so i was wondering if crimp could be a part of this????

any ideas?

i could use it...i have a ton of this powder,well, about 8lb's actually

thanks in advance.

JohnK · May 14, 2001, 04:56 PM

To much crimp can damage the bullet which will ruin accuracy. On smaller calibers that use less powder I don't think the crimp is going to have much effect on powder burn, other than increasing pressure if the bullet gets pushed into the case due to to light a crimp. Where you will see it more is on the big magnum calibers where a heavy crimp is needed to get those 25+ gr powder charges to burn. It's also needed on those rounds to keep the bullet from pulling out of the case on recoil.

I doubt your crimp is causing failures to extract, that's more likely either a problem with the extractor or possibly a very high pressure round that is causing the cases to stick in the chamber or a rough chamber that is causing the cases to stick. You don't say what gun, caliber or bullet weight you're using so I can't say wether the load listed is high. Do other loads have this problem or just this particular handload?

John
http://www.handloads.com

fedaykin · May 14, 2001, 06:05 PM

thanks, i am using a glock 19.

i also have a tungsten guide rod and a wolff 15lb spring in use.

i am using winchester 115gr jhp at 1.090 oal.
with 5.1 grains of winchester super target powder. it averages about 1180fps

i started with this handgun and unfortunately developed this load at the same time, so i have nothing to test it against. i sold a glock 19 to my buddy and he buys my reloads and has had no problems at all with the same load. i have an older glock (generation two) which did not have the slight rebate at the top, front of the breech block (at the locking area)...the newer glocks have this rebate...i noticed that the glock small frame 9mm pistols are the only glocks to have this modification from the factory.

i set the crimp right to where it makes an indentation on the bullet then i back off slowly (using lee factory crimp die) until there is no mark on the bullet after crimping.

well, i am going to test the extractor as well.
i don't notice any bulging of the cases at all.
when i have the malf, every time, the case is stuck perfectly front to rear, or with the base of the case on the breech face and the neck right on the back of the barrel right in the ejection port. like i said, sometimes the brass is throw directly to my front and slightly to the right, but almost right in front of me.

thanks again.

Walt Welch · May 14, 2001, 06:32 PM

fedaykin; go back and read your posts. Are you using a Winchester FMJ or JHP with your stated OAL???

It DOES make a difference.

Walt

fedaykin · May 14, 2001, 06:55 PM

hey sorry, jhp...

how big a difference would that make?
i know it would take more powder to drive jhp, but other than that i would not know.

JohnK · May 14, 2001, 07:45 PM

Actually it could take less powder for the JHP assuming you loaded the rounds to the same OAL. The JHP has a hole in the end (obviously) making the OAL of a JHP bullet longer than a FMJ, which means if the cartridge OAL is the same the JHP is seated further into the case which will raise pressures.

It looks like WST is slightly faster than 231 based on data for other calibers in the Winchester loading manual. Winchester only suggests 4.8gr of 231 under their 115gr JHP but doesn't list an OAL. 1.09 is rather short - you can go out to 1.25" OAL in the 9mm - so it's possible with that combination that you're getting excessive pressures causing the loads to stick in the chamber. I'd expect you would see buldged cases if that were the case though.

Since the same rounds don't have a problem in your buddys gun I'm still thinking it's the extractor in your Glock that's causing the problem, but you might want to back down the powder charger just to be safe as well.

John
http://www.handloads.com

Walt Welch · May 15, 2001, 01:01 PM

What JohnK said.

What pressure a given load generates is dependent on the amount of bullet seated into the case.

OAL is an INDIRECT measure of this property. It is used as a convenience.

To determine depth of seating, measure case, bullet, and OAL. [case + bullet] - OAL = seating depth.

Be careful. A change of 0.035" in seating depth in the 9 x 19 can change a safe load into a very dangerous one.

Walt

May 14, 2001, 06:05 PM	#3
fedaykin Member Join Date: September 10, 2000 Posts: 39	type 2 malf thanks, i am using a glock 19. i also have a tungsten guide rod and a wolff 15lb spring in use. i am using winchester 115gr jhp at 1.090 oal. with 5.1 grains of winchester super target powder. it averages about 1180fps i started with this handgun and unfortunately developed this load at the same time, so i have nothing to test it against. i sold a glock 19 to my buddy and he buys my reloads and has had no problems at all with the same load. i have an older glock (generation two) which did not have the slight rebate at the top, front of the breech block (at the locking area)...the newer glocks have this rebate...i noticed that the glock small frame 9mm pistols are the only glocks to have this modification from the factory. i set the crimp right to where it makes an indentation on the bullet then i back off slowly (using lee factory crimp die) until there is no mark on the bullet after crimping. well, i am going to test the extractor as well. i don't notice any bulging of the cases at all. when i have the malf, every time, the case is stuck perfectly front to rear, or with the base of the case on the breech face and the neck right on the back of the barrel right in the ejection port. like i said, sometimes the brass is throw directly to my front and slightly to the right, but almost right in front of me. thanks again.

May 14, 2001, 06:55 PM	#5
fedaykin Member Join Date: September 10, 2000 Posts: 39	whoops hey sorry, jhp... how big a difference would that make? i know it would take more powder to drive jhp, but other than that i would not know.

May 14, 2001, 02:37 PM	#1
fedaykin Member Join Date: September 10, 2000 Posts: 39	so, can anyone tell me how too much crimp can be bad and how too little crimp can be bad? what does the proper crimp help do besides the obvious, headspace and bullet compaction on feed ramp. how does it effect powder burn, pressure, cyling of the weapon. i think i need to move to another powder i am using wst with 5.1gr at 1.090 oal. i am using a winchester fmj bullet. i use a wolff spring at 15lb if i have a full magazine i get a type 2 malf (failure to extract. i can see brass dings on the forward ejection port and the brass gets thrown forward at times. this load chronos at 1180fps though. so i was wondering if crimp could be a part of this???? any ideas? i could use it...i have a ton of this powder,well, about 8lb's actually thanks in advance.

May 14, 2001, 04:56 PM	#2
JohnK Senior Member Join Date: May 12, 2001 Location: Duvall, Wa Posts: 552	To much crimp can damage the bullet which will ruin accuracy. On smaller calibers that use less powder I don't think the crimp is going to have much effect on powder burn, other than increasing pressure if the bullet gets pushed into the case due to to light a crimp. Where you will see it more is on the big magnum calibers where a heavy crimp is needed to get those 25+ gr powder charges to burn. It's also needed on those rounds to keep the bullet from pulling out of the case on recoil. I doubt your crimp is causing failures to extract, that's more likely either a problem with the extractor or possibly a very high pressure round that is causing the cases to stick in the chamber or a rough chamber that is causing the cases to stick. You don't say what gun, caliber or bullet weight you're using so I can't say wether the load listed is high. Do other loads have this problem or just this particular handload? John http://www.handloads.com

May 14, 2001, 06:32 PM	#4
Walt Welch Senior Member Join Date: November 3, 1998 Location: Alamo, CA Posts: 424	fedaykin; go back and read your posts. Are you using a Winchester FMJ or JHP with your stated OAL??? It DOES make a difference. Walt

May 14, 2001, 07:45 PM	#6
JohnK Senior Member Join Date: May 12, 2001 Location: Duvall, Wa Posts: 552	Actually it could take less powder for the JHP assuming you loaded the rounds to the same OAL. The JHP has a hole in the end (obviously) making the OAL of a JHP bullet longer than a FMJ, which means if the cartridge OAL is the same the JHP is seated further into the case which will raise pressures. It looks like WST is slightly faster than 231 based on data for other calibers in the Winchester loading manual. Winchester only suggests 4.8gr of 231 under their 115gr JHP but doesn't list an OAL. 1.09 is rather short - you can go out to 1.25" OAL in the 9mm - so it's possible with that combination that you're getting excessive pressures causing the loads to stick in the chamber. I'd expect you would see buldged cases if that were the case though. Since the same rounds don't have a problem in your buddys gun I'm still thinking it's the extractor in your Glock that's causing the problem, but you might want to back down the powder charger just to be safe as well. John http://www.handloads.com

May 15, 2001, 01:01 PM	#7
Walt Welch Senior Member Join Date: November 3, 1998 Location: Alamo, CA Posts: 424	What JohnK said. What pressure a given load generates is dependent on the amount of bullet seated into the case. OAL is an INDIRECT measure of this property. It is used as a convenience. To determine depth of seating, measure case, bullet, and OAL. [case + bullet] - OAL = seating depth. Be careful. A change of 0.035" in seating depth in the 9 x 19 can change a safe load into a very dangerous one. Walt