Too much crimp

[michael.birdsley]

First time reloading extreme plated bullets in 9mm 115 RN. Is this too much taper crimp? It's only crimping about .0025 but, definitely deformed the bullet a bit. Only loaded two. So if they arnt good it's not a big loss http://uploads.tapatalk-cdn.com/20160202/642b0f7205c57e40847e09f7b50b7455.jpghttp://uploads.tapatalk-cdn.com/20160202/cd71fce4c129ca34aec54f0a26b0de48.jpg

[michael.birdsley]

http://uploads.tapatalk-cdn.com/20160202/48d1914756d57c838d9e64efbacae244.jpg first photo was of a un crimped bullet

[runfiverun]

I'd say that's too much.
the first one [un crimped] is closer to my crimp, I basically iron the case flat against the bullet.
you'll end up near 376 depending on your cases thickness.
[bullet diameter times the case thickness twice.]
you build the neck tension into the round with your size die, and your flair die just opens the case mouth.
the seating/taper die puts it all back flat again.
remember that the round headspaces on the case mouth.

[JeffinNZ]

HA. That ain't nothing. I bought a Hornet recently for number one daughter and with it came a full box of Federal 33gr TNT loads. Couldn't keep them on a sheet of A4 at 100m. Pulled the ammo down to recover the cases and here are the bullets. Aside from just about no bearing surface look at the crimp mark.

159783

[bruce drake]

Wow Jeff! Send that picture to Federal and let them know they've screwed the pooch on quality control!

[mdi]

Although the first pic looks OK, the pic of the bullet shows definite overcrimping. For my semi-autos I don't "crimp" any reloads. I just use a taper crimp die to straighten out the flare in the case mouth (yep, I flare the case mouths for both jacketed and lead). Neck tension is enough to keep bullets in place in 3, 9mms and 2, 45 ACPs. Hint; just use enough crimp, de-flare, for the rounds to pass the "Plunk Test"...

[JeffinNZ]

Wow Jeff! Send that picture to Federal and let them know they've screwed the pooch on quality control!

Federdal don't load this bullet anymore. They use the 30gr 'green' bullet with the longer bearing surface.

[michael.birdsley]

Ok thanks guys just trying to figure out the idiosyncrasy of the plated bullets.

[swmass]

I've loaded thousands of plated bullets in 9mm before switching to cast. I never gave them a real crimpin.. I used the lee FCD and just gave them a kiss of crimp in fear of cutting the plating. You probably already know that crimping doesnt hold the bullet in, so you dont need to go real heavy like you would on a 357 barn burner.. just give em a kiss of crimp and if they're shootin accurately just roll with it. The second picture with the crimped round is definitely over crimped. Just give em a light crimp so that the case mouth has just a sliver of lighter colored brass where the crimp has been applied, about 1/3 of what you've got right now and you should be fine.

[michael.birdsley]

Although the first pic looks OK, the pic of the bullet shows definite overcrimping. For my semi-autos I don't "crimp" any reloads. I just use a taper crimp die to straighten out the flare in the case mouth (yep, I flare the case mouths for both jacketed and lead). Neck tension is enough to keep bullets in place in 3, 9mms and 2, 45 ACPs. Hint; just use enough crimp, de-flare, for the rounds to pass the "Plunk Test"...

First pic was actually a un-tapper crimp bullet

[mdi]

First pic was actually a un-tapper crimp bullet
That's why it looked good. My semi-auto reloads are "crimped" just enough to allow good chambering, and most of the time it's difficult to see any "crimp"...

[GWM]

In an autoloader there's the risk of boolits beeing pushed back into the case during recoil, in the magazine.

Check for this to happen. If not, there's enough crimp.

[cherokeetracker]

HA. That ain't nothing. I bought a Hornet recently for number one daughter and with it came a full box of Federal 33gr TNT loads. Couldn't keep them on a sheet of A4 at 100m. Pulled the ammo down to recover the cases and here are the bullets. Aside from just about no bearing surface look at the crimp mark.

159783

This looks exactly like a profile crimp. It is a combo of a tapered and roll crimp. It is used sometimes for ammo that is going to be used in full auto and semi auto use. Oh and sometimes in NON Lead bullet use.
Why would this type of crimp be used? It supposedly does not allow bullet jump or movement such as a tapered crimp would , for example when you jack a round into the chamber, then remove it later. Next day you rack it into the chamber again. This repeated action causes the bullet to keep going deeper into the case. I have seen this mostly with 45 ACP ammo. Standard ammo, this would not be so bad, but some Plus P ammo would not be good. Never heard of anyone blowing themselves up from this, but some LE guys have commented about that first round being more powerful, and throwing their POI off. This was the end result of them racking the slide and keeping that one bullet on top of the magazine. Simple solution is to rotate ammo.
But let me point out that this looks like the machine or Press that was doing this, was out of adjustment, and was crimping too much. I can't post photos here, but if I could, I would show you that the same thing ( or look ) on a twenty caliber bullet. The die was out of adjustment and looked this bad or worse. And the same thing happens to groups. There is not groups but patterns.

[35remington]

Apparently no one here has seen 17 HMR bullets.

[cherokeetracker]

Apparently no one here has seen 17 HMR bullets.

That is a heeled bullet in the 17 HMR the 22, and the 22 mag with a profile crimp.

[fredj338]

In an autoloader there's the risk of boolits beeing pushed back into the case during recoil, in the magazine.

Check for this to happen. If not, there's enough crimp.

A taper crimp won't hold the bullet unless you over crimp so much it forms a ledge. No, proper neck tension prevents bullet setback in any semi auto.
Yes, that is too much crimp. measure the base, you'll find it is now quite a bit smaller than when it went in. Factory pistol ammo is notorious for over crimping, why it tends to not be as accurate.

[michael.birdsley]

So I double checked my last batch of 50 and over crimped those a little also. I didn't really understand the ker-plunk test so read up on it more.I did the ker-plunk test on the last 50 and thought they passed. but, than I spun them around in the barrel and about half hung up a bit. Took some factory rounds and rounds I didn't crimped as hard and did the ker-plunk test and spun them in the barrel and they did not hang up. Being able to spin freely in the barrel is a good indicator of proper head spacing?

[paul edward]

Over crimping can cause swelling of the case, increasing it's diameter and making it too large to chamber correctly. While this is more likely to happen with thin walled cases, it can happen with almost any brass.

[35remington]

17 HMR does not have a heel, rather a vicious crimp approximating the one on the Federal TNT bullets in the photo.

While a very heavy taper crimp forms a ledge in a cast lead bullet it does not help jacketed bullet retention as the leading edge is still rounded ish rather than sharp.

[cherokeetracker]

[QUOTE=35remington;3532197]17 HMR does not have a heel, rather a vicious crimp approximating the one on the Federal TNT bullets in the photo.

You are right the 17 HMR and the 22 mag does NOT have a heeled bullet. They both use a profile crimp.

[David2011]

Michael,

The spec on the neck diameter is .380". Measure your case necks and adjust the taper crimp die to give that size. I measure a hair behind the mouth to avoid any burr on the mouth that would make the measurement inaccurate. Seat a couple of bullets and pull them to see if they're damaged.

Another thought- don't flare the necks any more than necessary to get the bullets started into the mouths. That will help maintain proper neck tension.

David

[michael.birdsley]

Michael,

The spec on the neck diameter is .380". Measure your case necks and adjust the taper crimp die to give that size. I measure a hair behind the mouth to avoid any burr on the mouth that would make the measurement inaccurate. Seat a couple of bullets and pull them to see if they're damaged.

Another thought- don't flare the necks any more than necessary to get the bullets started into the mouths. That will help maintain proper neck tension.

David

So when looking at the print. The spec for any cartridge at the case mouth is what I should crimp too? After seating a 9mm round my nominal case diameter is .377-.3765. When I crimp it only takes it to .376 some rounds will be 375 but, dosent look like I am crushing the bullet. Is there a SAAMI book to get +- allowed on the spec of .380. So I should flair the case more untill it is .380?

[mongoose33]

I've shot a lot of plated bullets and while the ideal is to just straighten the case wall back to parallel, a little bit of dent in the side of the bullet doesn't, in my experience, change much.

Unless you have evidence of extreme inaccuracy or see pieces of plating flying off, what I saw in the pic is ok. I would back off a bit, but I'd shoot those and expect them to perform.

[michael.birdsley]

This looks exactly like a profile crimp. It is a combo of a tapered and roll crimp. It is used sometimes for ammo that is going to be used in full auto and semi auto use. Oh and sometimes in NON Lead bullet use.
Why would this type of crimp be used? It supposedly does not allow bullet jump or movement such as a tapered crimp would , for example when you jack a round into the chamber, then remove it later. Next day you rack it into the chamber again. This repeated action causes the bullet to keep going deeper into the case. I have seen this mostly with 45 ACP ammo. Standard ammo, this would not be so bad, but some Plus P ammo would not be good. Never heard of anyone blowing themselves up from this, but some LE guys have commented about that first round being more powerful, and throwing their POI off. This was the end result of them racking the slide and keeping that one bullet on top of the magazine. Simple solution is to rotate ammo.
But let me point out that this looks like the machine or Press that was doing this, was out of adjustment, and was crimping too much. I can't post photos here, but if I could, I would show you that the same thing ( or look ) on a twenty caliber bullet. The die was out of adjustment and looked this bad or worse. And the same thing happens to groups. There is not groups but patterns.

I think this is what I was doing to the cases. Roll crimping and than tapper crimping on accident my fault. Tried sizing the crimp to .380 but, it wouldn't flatten the case mouth out, acurracy suffered. I don't think I was flaring the case enough. Best accuracy is crimping about .376. Checked my factory ammo and it all runs about .376-.378. But, now I'm getting fail to ejects with me reloads so I'm going to try bumping up a grain or two.

[philzilla]

That pic is great