How much crimp?

[bigarm]

I know I have seen this on here before, but can't seem to find it. I will be loading 200 grain Black Bullets for an STI Edge at about 1.18. I have read to use a very small taper crimp to avoid damaging the coating. Any ideas of the measurement I should be looking for? My plan (they never work out) is to get the 550 finished setting up tomorrow and begin loading 40 so any help would be appreciated.

[leath4m]

I only crimp enough to knock the bell out. And I don't confess to know anything about .40 cal. But I do know most damage is done when you seat and crimp in the one die. Usually the crimp will start before the pill is seated, which can peel a layer off.My .38 Super projectiles have a light ring around them when pulled. Hope this helps.

[LikesToShoot]

Agree with above. Just crimp to remove the bell created to allow seating the bullet. Make sure the cartridge will pass the "plunk test" in your barrel.

[Hi-Power Jack]

There are specific measurements for ideal crimp - but didn't work for me.

I used trial & error to make sure I had removed enough belling to get the

cartridges to seat properly in the chamber, but not too much that the

overcrimping affected accuracy -

Good news is, that I set my 9mm crimp up about 8 years ago and have

NOT had to change it since.

[DougCarden]

Bell the case enough that the bullet does not get the coating scraped off when seating. Then make a dummy round and start adding crimp to the round until you can drop the round into your barrel and it drops back out freely when turned over. That is all you need. No sharp edge on the case mouth.

DougC

[razorfish]

Change the words "Taper Crimp" to "Flare Removal".

For an exact measurement, take you bullets and measure the width (diameter) at the base (or where the bullet is meeting the top edge of the case). Now measure the thickness of brass at the opening and double the measurement.

Again, width of bullet + two times the thickness of the brass. This total will be measurement you should have after crimping (removing flare).

Now pull a bullet and make sure no coating is getting damaged. If you're getting any damage to the coating and your crimp measurement is correct, add a little more flare. Easy.

Edited July 21, 2014 by razorfish

[drewzter]

Change the words "Taper Crimp" to "Flare Removal".

For an exact measurement, take you bullets and measure the width (diameter) at the base (or where the bullet is meeting the top edge of the case). Now measure the thickness of brass at the opening and double the measurement.

Again, width of bullet + two times the thickness of the brass. This total will be measurement you should have after crimping (removing flare).

Now pull a bullet and make sure no coating is getting damaged. If you're getting any damage to the coating and your crimp measurement is correct, add a little more flare. Easy.

That's what I do for .40. .45. 9mm. Etc

Sent from my iPad using Tapatalk

[bowenbuilt]

If you run it into the taper crimp die and feel any resistance at all toward the end of its travel you are probably over crimping. It will get tight as you are sizing down the bullet diameter but not if you are simply straightening out the case mouth.

[jcc7x7]

.001 to .002 is what I use for Bayou's and SnS (same coating) coated bullets in 9, 40 and 45.

Make sure they drop "plunk" into your camber

[bigarm]

I had to crimp more than I thought I would like to in order to get reliable feeding and chambering of the rounds, but I seem to have it now.

[LikesToShoot]

I load on a 550. Once I have determine COL for whatever specific bullet I am using it whatever caliber I am loading for I seat the bullet to that COL.

I completely back of the Lee Factory Crimp die and pull the handle to push that cartridge into the crimp die then lightly screw the crimp die until it just touches the cartridge. Lower the handle, to pull it away from the crimp die, and turn the crimp die in another 1/8 of a turn and pull the handle again to "remove the bell". Now test the cartridge in the barrel chamber for the "plunk test". If it passes, GREAT, if not I add another 1/8 turn at a time until it passes.

No pulling bullets and measuring anything for me. Due to the variations in brass thicknesses (I use mixed range brass 99.9% of the time) I don't care what the measurement is for action pistol ammo.

Precision shooting is a completely different game and requires additional attention to details.

YMMV.

Add that I don't go nuts on adding crimp to remove the bell, I can't remember turning it down much more than 1/8 to 1/4 of a turn.

I recheck after I load the 10th round and again at 100 when I'm refilling the primer tube and checking the powder charge weight. These 100 rounds get's added to the BIG ammo can if it passes these checks. Then are repeated for the next 100 rounds.

If I discover a problem during the crimp / powder re-testing I have limited my suspect ammo to a 100 count batch and not a large ammo can of hundreds.

Edited July 22, 2014 by LikesToShoot

[BBQDawg]

I, too, shoot a 2011 in .40 S&W from Brazos. I shoot the 180gr BBI bullet and at least for my gun off the bench, I get my best accuracy at about 1.185-6 OAL with about a .420-.421 crimp using mixed brass. I put very little bell in the crimp when loading, just enough to seat the bullet.

[not4you2know]

I, too, shoot a 2011 in .40 S&W from Brazos. I shoot the 180gr BBI bullet and at least for my gun off the bench, I get my best accuracy at about 1.185-6 OAL with about a .420-.421 crimp using mixed brass. I put very little bell in the crimp when loading, just enough to seat the bullet.

I use the same crimp in all 2011s I have. With MGs, BBI, and Blue Bullets.

Edited July 22, 2014 by not4you2know

[tac_driver]

I use .423 in my Glock 23 OEM barrel

with 180gr FP S&S Casting High-Tech coated bullets

bullets are .401 diameter

Win case walls are .011

Using a OAL of 1.125"

Rounds are grouping at 1.7"

at 15 yds. with Power Pistol powder

[fastphil]

Remove the bell. Pull the bullet, verify there is no more than a faint line in the projectile from the case. The crimp groove in the projectile should measure no more than .399.