158 grains FMJs with no canelure

[CWS&W]

I found some RMR 158 grain FMJ RNFP. The jacket is brass instead of copper and there is no canelure. 12.5 gr of 2400 with a light crimp die that leaves a small ring indentation on the bullet. It does grow a little longer if it stays in the bottom of the magazine for more than 6 or 7 shots on my ruger 77/357. Someone told me I should taper crimp instead of roll crimp. Anyone have experience with this kind of bullet?

Sent from my SM-G781U1 using Tapatalk

 

[BLUEDOT37]

I've never used that particular bullet or shot 357 from a rifle but I've dealt with the issue you're asking about.

Have you measured those bullets with a micrometer (verses a caliper) to see precisely what their diameter is?

Bullets without a cannelure should be taper crimped.

If that doesn't stop them from jumping crimp then you might need to look at increasing the seated bullet-case tension.

Some sizing dies size a tad smaller than others. If you have a choice between two, use the one with the smaller diameter.

Use the absolute minimum flaring/bell-mouth to get the bullet started seating.

Some case have thinner walls than others. If you have a choice use the thicker one.

As a last option, with cartridges that it can be done with, I slightly deep seat the bullet so that the case mouth is just above the ogive & at a slightly smaller diameter of the bullet. (Obviously this can't be done with all bullets or cartridges & COAL" needs to be considered.)

Your taper crimp will slightly curve the case mouth over the bullet. It only takes a few thousandths smaller diameter to achieve the extra grip needed.

But you can only do it if you have empty space in a "larger than needed volume" case & you need to reduce your powder charge proportionally to keep the pressure where you want it.

I can keep bullets without a cannelure from jumping crimp in my high recoil revolvers with this technique.

.

 

[STORMINORMAN]

With any load for a 357 Magnum in a bolt action rifle you are probably anticipating and desiring (?) greater pressure and performance than from a pistol.or revolver.

As such, bullet design and crimp become more relevant, IMHO. A canelure certainly helps: especially as you do not want any bullets you load to walk forward or backwards.

Your load is really not near MAX for 158g: not like using 16gr of H110. You might want to consider using a different bullet for rifle loads? Or rethink your crimp. I have used a LEE 38/357 collet style crimp die with good results in this caliber.

The crimp is crucial on higher velocity loads in pistols and revolvers: for many carbines/rifles it can even be even more so...

Cheers!

 

[Capt. F.]

If you have a large quantity of these bullets you might want to try Googling cannalure tools. May be the solution you're looking for.

 

[Cdog]

It may require a bit more pressure than you're accustomed to applying to your .357 rounds with a cannelure, but a Lee Factory Crimp Die should easily accomplish the task.

 

[Nevada Ed]

With a "Smooth" wall bullet...........

there are two things that help prevent bullet creap.

One is a crimp and the other is less powder.

The type of crimp can damage a bullet if not done correctly and
maybe cause poor accuracy, so you do need to see what works out best for you in your weapon.

I hope these loads are for target work, that can adjusted to work.

Good luck.

 

[robertrwalsh]

I have shot a fair number of them recently. A decent crimp and NOT a full power load does the job. I do have a cannelure tool and may use it if I ever have need of full power loads with this bullet.

 

[Old Corp]

My method of assembling nearly ALL my magnum-level loads may help (.357,.41, .44 and hot .45 Colt).
I DON'T use the factory-supplied expander plug for belling the case mouth.....

I use an old RCBS .30 M1 Carbine expander (with the end ground off that used to hold the decapping pin - that's how they used to be set up)
Doing this bells only the case mouth and provides greater tension between the bullet and case body.
Yes, the result is a sort of 'wasp-waisted' loaded round, which hurts nothing at all.

For a crimp on a non-cannelured bullet, the Lee Factory Crimp die is a good idea already proposed.
In a pinch - I've made do with removing the decapping stem from my sizing die and bumping the round into that.
Works.

Good luck!

 

[bluetopper]

Just screw the die down a tad more and make a tighter crimp. You may put a slight ring around the bullet but it will be nothing in comparison to the scars the lands and grooves will put on the bullet after it is launched.

 

[Tim357]

Something else that can help is to completely de-grease the inside of the case before loading. Ever try to seat a bullet in a brand new Starline case?

 

[colt_saa]

The brass jacketed 158 FMJs that I use are actually manufactured by Armscor. These are traditional FMJ-RN.

WOW Rocky Mountain is showing over 132 Million of those currently availble

I have been using that Armscor projectile for years in my LAR Grizzly with it's 357 Magnum conversion

The solution to your problem is the Lee Collet Crimp die. It will form the cannelure as it crimps the cartridge (just one step)

You need to be careful when ordering the die that you do not end up with the 357 Magnum Lee FCD. This standard die has the carbide ring in it and imparts a roll crimp.

The 357 Magnum Lee collet crimp die is a different part.

357 Magnum Custom Collet Style Crimp Die - Lee Precision

The Factory is currently out of them, but the MSRP is just $16. You can probably find them on-line.

These used to be custom orders, but Lee now keeps several calibers as regular items

I collet crimp every handgun cartridge that Lee offers a die for. It is a godsend in loading the 357SIG with it's short neck

 

[gwpercle]

I use the taper crimp die from my 9mm Luger set to taper crimp the smooth sided bullets , loaded into 357 magnum . They hold , shot from Ruger Blackhawk 357 Magnum for all 6 shots .
Taper crimp works better on the smooth sided bullets than trying to force a roll crimp into a bullet that has no provision for roll crimping .
Taper crimping holds 9mm luger bullets and it will hold .357 bullets in the magnum and/or special cases with just a little die adjustment .
Gary

 

[CWS&W]

Using a Lee FCD, could I damage the case by putting a deeper cannelure?

Thanks for all your tips. It seems like there is no concensus on whether to paper crimp or roll crimp.
I will reduce my flaring though because I had it set up for Lead SWC so there is a little wiggle room.
I don't think I can seat the bullets deeper so that the case mouth is just above the ogive & at a slightly smaller diameter of the bullet with a 158gr bullet, though I do it with my 130gr truncated cones with great results.
I am not specially looking for max velocity or pressure, I'm just looking for the most accurate load possible using the components available at this time, hence the non cannelure bullets, it's all I could find. I just enjoy making holes in paper but I do like to feel a little pressure.
The 357 Magnum Lee collet crimp die looks like a possible solution I am going to look for one.

 

[STORMINORMAN]

It's a revolver: seat the bullet where you wish (as long as you don't load it too short)...

Cheers!

 

[Nevada Ed]

You might also try a few loads with just 11.7 grs of 2400 powder.......

this load shoots well for me, instead of 2400 at 1340 fps out of my 6" barrel.