How Much Taper (.380 ACP)?

[John from MD]

When you use a FCD, you back off the seating die so that it doesn't crimp but only seats the bullet. The FCD will put a taper crimp on the case and is fully adjustable by you.

 

[erwos]

OP, what kind of mags are you using in that 42? What you are describing is a weak magazine spring strength issue, not a reloading issue. Mag spring not keeping up with the slide (or bolt) is a classic issue leading to these kinds of malfs.

If you round doesn't chamber, that's a reloading issue.

 

[Mark K]

I'm sorry. It would help immensely to know what you are reloading on, as far as what press you are using.

Didn't think that would be critical. It's a Hornady Lock-N-Load Basic single-stage press.

The first rule of reloading any cartridge that has to be belled or flared is, never seat and crimp a round in the same stage.

I'm not following. Does that include "normal" expansion while doing "normal" reloading, when the expander die is used? Or does that mean when a cartridge has been belled or flared more than with the expansion die for some reason?

Because the belling I noticed after I'd pulled all the bullets was noticeably more than what I've always seen after using the expander die. Not sure why they would have belled that much when pulling with a collet...

In any case, after I re-seated the bullets, the case mouth diameter was still significantly more than spec, and they were failing the "plonk" test. So I ran all the rounds back through the seating/tapering die with the bullet seater screwed all the way back -- so all it was doing was tapering. I checked the first few rounds afterward, and they were within spec and passed the "plonk" test. But apparently not all of them, like the one in Post #3 above -- the mouth diameter is way more than spec... Like I wrote, it's 0.377", when spec is 0.373...

 

[Mark K]

OP, what kind of mags are you using in that 42? What you are describing is a weak magazine spring strength issue, not a reloading issue. Mag spring not keeping up with the slide (or bolt) is a classic issue leading to these kinds of malfs.

If you round doesn't chamber, that's a reloading issue.

They're OE Glock 42 mags. We've got four of them. However, I have installed Strike Industries +2 magazine extensions in three of the magazines:

https://www.brownells.com/magazines...-magazine-plate-for-glock-42-2-prod80857.aspx

That's because the stock 6-round mags really do have limited capacity and don't allow for a good grip.

The springs are stock, like they're supposed to be; so yes, it had occurred to me that they might be weak for the last two rounds. But the problems were occurring throughout the magazines, not just on the last couple rounds. I don't know whether longer springs are available anywhere...

I did use the fourth original 6-round magazine too, and I didn't notice that the reliability was any better with that...

 

[Biggfoot44]

The : Seat & Crimp in one stage vs Never Seat & Crimp in one stage vs Sometimes & It Depends is an eternal and endless debate among handloaders that will never have a definitive * All Encompassing * answer .

IF you so pursue , it is indeed possible to seat & crimp in seperate STEPS without an additional die . Heck that's how it was done for many decades before the Factory Crimp Die sprung from Richard Lee's fertile mind . ( Fwiw , there were other specialized Crimp Only dies before the FCD , most notably the Redding Profile Crimp Die ).

The old school method was to adjust your die so as to seat the bullet w/o applying any crip for your batch of rounds . Then re adjust your die to apply desired crimp , without the seating stem contacting the bullet , and run all your rounds thru that . Yes , that's a lot of fiddling with die adjustments .

And to reduce the semantically inducws confusion ; " Just squeezing the neck " etc is properly known as " Applying a Taper Crimp " . The two Most Common flavors of Crimps are Roll Crimp and Taper Crimp . ( There are other specialized and/ or historical types of Crimps , but we can disregard them for the purpose of this thread .)

The Cliche is Taper for autoloaders , Roll for Revolvers . And that is frequently opperative .

No,I can't specifically trouble shoot your rounds from a distance either . But the depth of Taper Crimp in the first pic does look notably light .

 

[erwos]

They're OE Glock 42 mags. We've got four of them. However, I have installed Strike Industries +2 magazine extensions in three of the magazines

This is your problem. You need stronger mag springs to run +2s. TTI has some. I bet that if you remove the extensions your problems will go away.

I mean, you're willing to go through some insane hassle from some rando at a club's comments about "taper"... humor me.

 

[U.S.SFC_RET]

So what's the "pushing method?" I assume pushing the seated bullet down against the bench, and seeing if it moves farther into the casing? How much pressure? In other words, how will I know if I'm happy with the taper?

When you have a bullet setback you run the risk of increasing pressure in that case. A big no no.
You want to ensure that bullet setback doesn't happen. Give the bullet a bit more than mediocre force, you don't have to stand on it you just want to make sure that your bullets will not move in the case. Believe me it happens more than you want them to. Just the other day a reloader at my range suffered a Kaboom because of bullet setback.

 

[Mark K]

This is your problem. You need stronger mag springs to run +2s. TTI has some.

TTI being Taran Tactical?

Worth a try... they're cheap enough... Will these do?

Though, like I said, I had the same feeding (and extraction/ejecting) problems with the one stock 6-round mag I was using...

I'll work on the taper too.

You know, I consider advice from anyone who seems competent, and whose advice seems reasonable. (Like you.) This "rando" ( -- not sure what that means, but I can guess) happened to be a sponsored competitive shooter who's been reloading for decades... Doesn't make him right, but I'll consider his advice...

*edit* I just ordered three of the springs.

By the way, any tricks for removing those damn' Glock base plates? I'm afraid of cracking the sides of the mag when squeezing them in to release the locking tabs...

 

[erwos]

TTI being Taran Tactical?

Worth a try... they're cheap enough... Will these do?

Though, like I said, I had the same feeding (and extraction/ejecting) problems with the one stock 6-round mag I was using...

Yes, those are the ones. There is no trick to removing the floorplates. Good luck.

I don't know what to tell you about your friend (I'm a semi-well-known gunwriter, does that give me any more credibility? lol), but nose-up failure to feeds are synonymous with magazine problems. If your rounds won't chamber, that is either a crimp problem or seating the bullet too far out for your barrel's chamber (ie, bullet hitting the rifling).

 

[John from MD]

Yes, those are the ones. There is no trick to removing the floorplates. Good luck.

I don't know what to tell you about your friend (I'm a semi-well-known gunwriter, does that give me any more credibility? lol), but nose-up failure to feeds are synonymous with magazine problems. If your rounds won't chamber, that is either a crimp problem or seating the bullet too far out for your barrel's chamber (ie, bullet hitting the rifling).

I told him that in post #5 but he is sold on it.

 

[PowPow]

If you are looking for a rough chamber, you would be looking for 'frosted' cases. These are from my g20. The one in the middle is after polishing the chamber. The two on the outside are frosted. The chamber was so rough, I had to hand feed each round into the chamber. It could probably stand some more polishing, but for now, the gun runs and feeds fine.

Nice picture!

 

[Mark K]

I told him that in post #5 but he is sold on it.

Not at all. I'm just weighing all the advice I'm getting from different sources.

In Post #5 you thought the issue was loads that were too light, and you were recommending 3.3- or 3.4-grain loads. Which is over the maximum load of HP-38 recommended by Hodgdon and Lee. My loads are currently 3.1 grains, which is the max recommended by those two companies.

Unless you can convince me otherwise, I'm even hesitant to go to the 3.3 max grains recommended by Hornady, since they seem to be an outlier...

 

[Mark K]

Yes, those are the ones. There is no trick to removing the floorplates. Good luck.

Cool. Thank you.

The tabs I'm talking about on Glock magazines are these, on both sides of the baseplate:

They keep the baseplate from just sliding off when the button on the bottom is depressed. As far as anyone can tell, the sides of the magazine need to be squeezed together to get the tabs to clear. But I'm afraid of cracking the plastic. Any tricks?

 

[John from MD]

It's a locked breech gun. The loads you find in the load books are for blowbacks. The same thing happened when Ruger made the Blackhawk in .45 Colt. The only loads were for guns that had older metallurgy and the Blackhawk was made of 4130 steel. Later the books caught up and they have sections with loads for Blackhawk, TC Condender, XP100 etc.

If the people push the manufacures to develop loads for locked breech .380's then you will have loads for locked breech guns. Now they don't exist from the manufactuers to my knowledge. However, there are people like Ranch Dog, who became a specialist in .hot .380 and .44 Mag loads and has published tested data.

If you want to stay with blowback loads, then buy an extra recoil spring and cut coils until it runs for you loads.

 

[lazarus]

If the round is getting caught at a 45 degree angle, your problem is not with OAl. OAL problems on blowbacks usually will feed fine but they won't chamber all the way. You have a feeding problem from the magazine to the chamber. In this case, I believe you are loading your ammo too light and not getting full slide travel all the time. Go up to 3.3 or 3.4, it won't hurt anything.

Likely this. Not sufficient return momentum on the slide. In your case probably not a strong enough charge. You can also have TOO powerful a cart causing issues if the slide has too much velocity coming back. You can lose momentum slamming back. Both even with a good grip causing flip, as well as frame flex eating up energy on the recoil.

So sometimes with heavy +p loads you need a stronger recoil spring. Reduces frame bashing and help ensure proper return to battery (found that with some +p 147grs that were causing a lot of FTF. Swapped to a new captured recoil spring and went from every other round FTF to 4 in a magazine. Swapped to an 18# spring and 100% function for 2 mags (all I had handy to test)).

Anyway, I’ve seen that with 32acp on my Cz50. Gets hung up and then has a hard time feeding until I trip the magazine, reseat the bullet and drop the slide again.

I DID also have taper crimp issues (not enough). So I had bullet set back on a couple rounds, lower velocity than expected and terrible SD figures for my groups.

IMHO, not the recommended way to test, but I both do the bench test to ensure no setback and take my 6oz rubber mallet and tap on the bullet with modest forth (basically just bounce it on the tip a little. Not like actually whacking it).

I also load up a few dummies and run them through the gun several times. Check the COAL after that to see if they set back.

Learned the hard way...

 

[lazarus]

Cool. Thank you.

The tabs I'm talking about on Glock magazines are these, on both sides of the baseplate:

They keep the baseplate from just sliding off when the button on the bottom is depressed. As far as anyone can tell, the sides of the magazine need to be squeezed together to get the tabs to clear. But I'm afraid of cracking the plastic. Any tricks?

Yup. Squeeze hard.

If you don't have the Glock magazine disassembly tool, grab a pair of good sized channel lock pliers and a piece of cardboard or thin towel to reduce/keep from marring the plastic. Gotta squeeze hard. You won't break it, its very, very strong plastic. Obviously don't actively try to crush it, but I've gotta crank down hard on my 8" channel locks to compress the magazine body enough to get the base plate off. Have to do that while depressing the button on the baseplate to get it off.

 

[Mark K]

It's a locked breech gun. The loads you find in the load books are for blowbacks. The same thing happened when Ruger made the Blackhawk in .45 Colt. The only loads were for guns that had older metallurgy and the Blackhawk was made of 4130 steel. Later the books caught up and they have sections with loads for Blackhawk, TC Condender, XP100 etc.

If the people push the manufacures to develop loads for locked breech .380's then you will have loads for locked breech guns. Now they don't exist from the manufactuers to my knowledge. However, there are people like Ranch Dog, who became a specialist in .hot .380 and .44 Mag loads and has published tested data.

If you want to stay with blowback loads, then buy an extra recoil spring and cut coils until it runs for you loads.

Ah! That makes sense. Thanks.

Yes, I want to stick with blowback loads, because I've got other blowback .380 guns (Bersa 380CC, Walther PPK/S).

I would assume, though, that "normal" commercial .380 ACP ammo is designed for blowback guns, which -- as you say -- are the vast majority of .380s. The G42 must be designed to work reliably with those... No?

I'll stick with 3.1 grains of HP-38 for now, the max load according to most. And I'll change the mag springs when I get them. And I'll narrow the taper a bit. If all that doesn't work, I'll consider getting a lower-weight spring for the G42. I'm always hesitant about doing that, because the stock spring is designed for the gun, and I'm afraid I'll start getting other function issues...

 

[Mark K]

Yup. Squeeze hard.

If you don't have the Glock magazine disassembly tool, grab a pair of good sized channel lock pliers and a piece of cardboard or thin towel to reduce/keep from marring the plastic. Gotta squeeze hard. You won't break it, its very, very strong plastic. Obviously don't actively try to crush it, but I've gotta crank down hard on my 8" channel locks to compress the magazine body enough to get the base plate off. Have to do that while depressing the button on the baseplate to get it off.

OK, that's what I've been doing -- thanks. Channel locks or other ways to squeeze the sides of the mag body. I assume a Glock tool just does the same thing...

I've toyed with the idea of just grinding those tabs off -- seems like the base plate button would hold well enough, like on other magazines. But I don't want to screw around with that, since I don't have to do this very often...

 

[outrider58]

If you can stick a dowel in the hole while firmly holding the mag horizontally on the edge of the table, tap the dowel downwards. It's a bit of a balancing act.

 

[John from MD]

Glock mags suck, especially for those of us with arthritic fingers.