crimping RMR plated bullets

[Buck13]

I've been loading plated bullets for my revolvers for a while, but I don't have much confidence that I'm doing it right. When crimping plated bullets that have a cannelure of no real reduced diameter with a ring of hash marks, can you really get an effective "heavy" crimp for slow powders?

And how do you judge your crimp? With this sort of cannelure, it seems like the crimping force goes up very fast with small downward adjustments of the die, which is no surprise since the case has nowhere to go relative to crimping into a big groove in a cast bullet. Is a caliper measurement of the case mouth reliable, or each time you set the die do you need to pull a bullet to verify that you haven't cut through the plating, or just try to develop a feel for how much ram force it takes to mangle (or not) the plating??

Finally, I would think if you want to crimp into the side of the bullet like this, it would be best to seat to the desired OAL without crimping, then back out the seater plug and crimp without moving the bullet at the same time. Yes or no? I do it as two steps unless I'm doing no more than flattening down the flare or just a tiny bit more.

 

[ku4hx]

How do they perform for you? If you get complete powder ignition and the cases don't back away from the bullets under recoil, I'd say you technique works.

Unless the bullet has a pronounced crimp ring and you can use a strong roll crimp, proper crimp is mostly know by how well the cartridges perform. A roll crimp on a cast bullet is easy to see. It's a little harder on a jacketed bullet but you can still see an adequate crimp.

Most of my plated bullets are loaded in 9mm, 40, 45 and 38 and 44 special. Neck tension alone works well for them. I had one .44 Magnum expander ball I have to have turned down to increase neck tension for H110, maybe if your having problems a small expander ball would help.

 

[Walkalong]

Heavy taper crimp on a Powerbond 125 Gr bullet in a .357 load.

Medium Taper Crimp on an X-Treme 200 Gr FP in .44 Spl

 

[Buck13]

How do they perform for you? If you get complete powder ignition and the cases don't back away from the bullets under recoil, I'd say you technique works.

I just got the RMRs a couple of days ago, and haven't done anything with them yet. I've burned a thousand or so Xtremes in revolvers and haven't had any problems, but the noses of those bullets were short enough relative to the cylinders that they would have had to pull half-out of the cases to tie up the action, and I never took one out after 5 rounds to inspect it, so they could have slipped a little without me knowing. Seating force has been OK, and if I bear down on the case with my thumb, they don't slip.

A lot of those were not particularly hairy loads, but I have shot a number of Xtreme 240s over 20 gr. 2400 or 23 gr. 4227 in .44 magnum. Accuracy of those near-max loads was kinda disappointing. I may have just done a crappy job with those shooting sessions, but it was my suspicion that the bullets weren't up to it, since lighter loads or heavy loads with XTPs both generally shot better. I assumed that's a case of "you get what you pay for." I doubt the crimp is to blame, but I haven't tried to experiment with it. Maybe I'm wrong; hence this thread.

 

[Buck13]

Walkalong, in the close-up of the .357 it looks like the hash marks bend inward under the crimp. Is that an artifact of photography, or do they look like that to your eye? If that's real, I think I'm not crimping nearly as hard as you are.

 

[Walkalong]

it looks like the hash marks bend inward under the crimp. Is that an artifact of photography, or do they look like that to your eye?

It is indeed "tapered" inwards. I set up the die for a heavy crimp, and use spacers for lighter crimps. My very light crimps are not noticeable to the naked eye or the calipers.

 

[Buck13]

Thanks. I don't have any true taper crimp dies yet, but I will try being a bit more aggressive with what I have.

 

[Sunray]

Forget the cannelure and the crimp. You only need to crimp heavy recoiling loads. Plated bullets are loaded with cast bullet data. No crimp is needed.

 

[buck460XVR]

When crimping plated bullets that have a cannelure of no real reduced diameter with a ring of hash marks, can you really get an effective "heavy" crimp for slow powders?

IMHO, It's kinda a moot point. Even those with a cannelure and heavy plating are generally not designed for those top velocity loads using slow powders. They are generally meant for medium velocity or plinking loads using faster powders that are less critical of crimp. Plated bullets are not meant for hunting, nor are they deigned for SD/HD. They are meant for a cheap way to target shoot. That said, using a roll crimp and crimping without deforming, into the cannelure of plated bullets, is all you really need for them.

 

[Walkalong]

You only need to crimp heavy recoiling loads. Plated bullets are loaded with cast bullet data. No crimp is needed.

Using plated bullets with lead data only can lead to stuck bullets in some applications, especially when starting at the bottom, or when using light data for soft lead or target data.

Berrys has two things on the website about plated bullets.


From the FAQ list.


"How do I load Berry's Preferred Plated Bullets"

We do not research or publish the load data, but you can use any published load data for a jacketed or lead bullet as long as it is the same weight bullet. Any of the load data books or the powder manufacturers’ website should have that information for you, as long as you keep them under 1250 fps for our standard bullet or 1500fps for the bullets designated as TP (thick plate).

"Load Data for Berry's Preferred Plated Bullets"

Currently published load data is limited to some calibers by Accurate, Western Powders and Hodgdon. We are working with these companies to get data published for all of our bullets.

We recommend using hard cast load data or start with mid-range jacketed data. Make sure data is below 1250fps unless you are using a Thick-Plated bullet that we list a higher max velocity for like the 9mm 124gr HBRN-TP that can be shot to 1500fps in open class guns like a .38 Super. Keep in mind that since our plated bullet has the same pressure curve as a hard cast bullet, the published cast data will be very close to what you will get with our plated bullets. If you use Jacketed data with our plated bullets you can get from 5% - 8% increase in velocity using that data.

Ranier has this on its website:

Load Data

Rainier recommends using commercially published jacketed bullet load data when loading our bullets. There is no need for adjustment when using jacketed bullet load data. Our bullets are jacketed using an electroplating process and are softer than traditionally jacketed bullets. Be sure to use only load data that is published in a reputable reloading manual.

We recommend a starting powder charge directly between the listed minimum and maximum load.

A slight roll or taper crimp may be used with our bullets. Over-crimping plated bullets may result in decreased accuracy, and fragmentation of copper plating.

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