Does everyone roll crimp their lead cast bullets for use in magnum cartridges?

Every cast bullet I have for revolver cartridges is a SWC with a crimp band, so yes, I roll crimp.

If you're going to load full magnum power, you pretty much have to.
For moderate loads I sometimes use a taper crimp.

Light to mid-range loads you can use a taper crimp or a light roll crimp. For heavier loads, a firm roll crimp is key to keeping the bullets from pulling from the cases and for proper powder burn with slow burning powders.

Yes. That groove is there for a reason.

Well.........yes!

Lee Carbide Factory Crimp Die....for everything jacketed, plated or cast.

And they all get the same heavy crimp regardless of the load. Have found that it helps the powder burn better and cleaner and does nothing to shorten brass life.

Bob

Yup. Yes I do.

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Expect the unexpected

Oh boy I do too. The flaming will commence!

Either the Lee crimp die or a roll crimp yep. For a 45 ACP a taper crimp.

Yes I roll crimp cast bullets. But I don't have any magnum guns. I can get my regular caliber guns to recoil all I can stand!

Best answer.

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Certified Curmudgeon

Was crimping my 180gr cast lead with a Lee Factory Crimp Die and getting very inconsistent velocities when using max loads of 2400 and H110. Went to a roll crimp and solved the problem. Now getting very consistent velocities and slightly better accuracy. Still use the Factory Crimp on target loads with no problem.

A medium roll crimp seems to suit my heavy loads. Maybe if I used a powder like H110/W296 a heavy crimp would help.

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"He was kinda funny lookin'"

My 44 Magnum bullet diameter is .433 rather than .430 so I am wondering if enough neck tension would be present not requiring a roll crimp?

It would depend on your load, maybe, maybe not. The 44 magnum is know to jump a crimp with heavy loads especially with a lite weight revolver.

9mm and 45 acp get a taper crimp, all other roll. For 38/357 44 and 41 I don't even have taper crimp dies. I also only use cannelure bullets for this calibers, so off course medium roll crimp!

Your 44 Mag die set doesn't crimp? You don't have to use a heavy crimp. Even a light of moderate crimp is probably better than nothing.

What powder are you using? How hot are your loads? What gun are you shooting? All these questions are pertinent to be able to give any useful answer.

I mean't with the larger diameter bullet .433 there will be more neck tension with it than there would be with a .430 diameter bullet so I was asking if it would be possible not to have to roll crimp the cast bullets at all. My die set seats and crimps both in one step but I do them separately. I am using H110 22.5 grains with 3/8 turn from once the die contacts the case mouth. I am shooting a model 29-2 6.5 inch barrel.

Even my light 148 HB and BB wc , .38 target loads get a light roll crimp.

Lead: light to heavy crimp, depending on the fps of the load.
Fast powders might get away with a medium crimp buy my
slow powder loads seem to do better at the top end with a heavy crimp.....
plus they usually get tighter groups and ES numbers.

No.

With a heavy-enough gun and a not-terribly-rough load, they probably won't pull out enough to lock up the gun, but they'll pull out some.

Look at it this way. You expand the case, and smush the bullet in. Great. Now the diameter below the bullet will resist bullet setback, because it's narrower than the bullet.

What diameter is the bullet above the bottom of the bullet? Probably the diameter of the bullet, after seating. The fact that the bullet started out as a .433" instead of a .431" or .430" doesn't matter.

Don't know about everyone, but all my cast revolver bullets, 357 and 44 Magnums, get positive roll crimps into their crimp groove. I've been reloading .44 Magnum since '88 and all my reloads, with cast or jacketed bullets, get a good roll crimp and I discovered Redding's Profile crimp mebbe 10 years ago and use it for my many of my 44s too...

Not a big deal. I've been using the "rule of thumb for crimping" for over 30 years and 90% of the time it works for me; bullets with a crimp groove or cannalure get roll crimps. Bullets without a crimp groove or cannalure get a taper crimp. K.I.S.S....

Just wondering, you say your bullets are .433", have you measured your cylinder throats? If your throats measure .431" the .433" bullet will exit the cylinder at .431"...

Yes. I do what Mikid does.

I also FCD (Lee Factory Crimp Die) my
Rifle Cartridges (.223, .222, .308, 30-06
.270). It usually has helped accuracy.
I believe powder burns more complete,
and neck tension is consistent cartridge to
cartridge.

45ACP is Taper Crimped always.

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We roll crimp cast leads just like jacketed when necessary. The Penn lead 375gr 458 WinMag is shown amongst others.

The Headhunter history exhibit/lecture at the MONH in NYC in ‘1955 had a book about shrinking things.

I use a heavy roll crimp on every revolver round I load that has a crimp groove. Doesn't matter if it's a lite plinking load for the 38spl of fullhouse loads for the 44mag.

I use a 2/1000th's to 3/1000's taper crimp on every bullet/caliber where the bullet doesn't have a crimp groove.

I roll crimp just enough to make sure my 1894C in 357 Mag doesn't hang up. Turns out a light crimp works fine since I shoot light loads. My brass lasts and lasts.

Forrest r, do you find a heavy crimp shortens brass life?

I have no idea. Some of the 38spl brass I have has been reloaded so much that the nickle plating has wore off. Others make it 9 or 10 reloads and the top edge starts to split.

2 years ago I did run into a problem with old weak 357 brass. Bought a new 686 and did test loads using 1x 38spl brass. Didn't take long to find loads that shot bugholes. Typical 6-shot groups @ 50ft.


Switched over to 357mag cases and started doing test loads. Kept getting groups like these @ 50ft.


The loads would try to group but I kept getting fliers. I started taking a look at my 357 brass. I started out with a 5 gallon bucket full of 357 brass. By the time I got done sorting it and tossing anything and everything that looked old/bad/worn, I ended up with a coffee can full. So I ordered 2,000 new pieces of 357 brass from starline. The groups went back to bugholes with no fliers with the sorted & new brass.

Some of those cases were so bad I wouldn't even call the hold they had on the seated bullets neck tension. I've crimped everything the same way since I started reloading in 1985. I learned how to reload from my brother who started reloading in 1973. He also used a heavy crimp.

Don't know if it's a good thing or not, just what I learned and still do to this day.

On rifle bullets I do like to use the lee collet crimp dies.

Well yeah,,, ya have to.

I bought 2000 357 Mag cases from Starline and am very pleased with how they're holding up. I have to believe that heavier crimp will cause cracked necks quicker than a light crimp. Probably not a big deal, but it could be.

Here's a link that covers crimping, some may find it interesting:

Crimping Revolver bullets

My cylinder throats are .4336 and my grooves are .4294 so this is why I went with a .433 bullet.

I don't use a taper crimp on revolver ammo. I use a light roll crimp on target or mid-level loads, and I use the beloved Lee Factory Crimp on the heavy loads.

I do not see a need to ever use a heavy crimp, but "light", "medium", and "heavy" are subjective when it comes to crimping.

I believe case neck tension should be adjusted for a firm grip on the bullet, so a heavy crimp is not necessary.

I never use 296/110 powder, but 2400 for my magnum revolver loads because it is easy to ignite and does not require a lot of resistance (that some believe comes from a heavy crimp) to get it lit.

Revolver ammo,I roll crimp and I must admit that I've got a heavy hand at it,quick or slow burning powder..It always worked for me so I won't try to fix something that's not broken.
On the other hand,for s-auto guns,my taper crimp is very light;kind of like a maiden kiss.I measure the thickness of the brass X2 and add the bullet diam. and crimp to that extent.My reasoning(I might be wrong here but it has worked for me for the last few decades)is that the s-auto handgun operates through a slim powerband and I'm better keep the operating pressures as close as the blue print says(in most cases,that blueprint having come out of that great genius,Mr.Browning).

I thought you supposed to anneal the case mouths every tenth reload or if a split appears you anneal the whole batch to try to save the rest them.

I would not recommend annealing pistol brass in my opinion.

you should use the proper sizing die to seat the bullet easy w/o much neck tension otherwise you will distort the cast bullet ruining accuracy. The Lyman M-dies seem to be best. I use a few cowboy sizers from RCBS and they are oversized enough.

Are you saying that it would be best to get a cowboy sizing/decapping die rather than the factory 44 mag sizing/decapping die because it will not size the brass down as much? They did send me a cowboy expandind die to help out with case mouth expansion.

I thought the cowboy dies were just for use with revolvers with a pre-war ll .454” bore which required a slightly larger bullet diameter for proper fit.

Rifle brass can be expensive and annealing will re-soften the work hardened case neck and shoulder areas. There may even be an advantage to accuracy and consistency of annealed rifle brass.

For pistol cartridges, the brass is much cheaper than rifle brass and it's just not worth the effort.

If the bullet has a cannelure, I roll crimp. If not, taper crimp.
Of course, this applies only to revolver cartridges. No roll crimping for semi auto cartridges.

That is dependent on the load and the firearm they are being assembled for.

Though most everything gets some kind of crimp. The type of crimp I use varies from a taper crimp to a roll crimp to even a collet crimp on some lead projectiles

I agree

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NRA Life
USPSA/IPSC

All lead lubed bullets need a crimp. There is little friction between a case mouth and a cast lubed bullet. You lube a cast bullet to prevent barrel leading by reducing friction, that lube also reduces friction in the case mouth. Revolver and rifle ammo needs a roll crimp. Semi-auto pistol needs a taper crimp; 380 acp, 9 mm, 40 S&W, 45 acp and similar cartridges.

Powder coated bullets should probably be crimped, but I have no personal experience with PC. At age 70, I have enough bullet lube material to supply my grand children. I got very tired of buying lube sticks for my bullet sizer. I didn't realize how much bullet lube an 8# block of bees wax (I bought 2 blocks to save on shipping) and a quart of liquid Alox makes. Three 3# coffee cans is a LOT of bullet lube. That was the first batch with 1 beeswax block.

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S&WHF 366

Light crimp on my 357 mag, and my DE 44 mag. A more "robust" crimp on my 460 XVR mag !

What he said. :-)

Have a blessed day,

Leon

I load lead semi wad cutter in 45C, 44 mag, 357 mag and 38 special.
They all get roll crimped.

Load up six. Fire and check the remaining rounds for jumping with a caliper. If the last one doesn't move. You are good to go.

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"He was kinda funny lookin'"

Yes, for .357 diameter jacketed bullets (which have a cannelure) and lead bullets (which have grooves), for both the .357 Magnum loads and the .38 Special loads.

Lee crimp die.

A mild crimp with the Lee die for copper plated bullets -- which do not have a groove -- and a still pretty mild crimp for coated bullets -- which have the grooves of the lead bullet underneath the coating. Just getting started with the coated bullets, but I don't want to cut through the coating and cause them to separate from the lead bullet as they leave the case.

Never had a bullet pull out of a case while in a cylinder.

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S&W Rover