Rcbs 357-180-sil

[Marlin Junky]

Anyone have experience with RCBS 357-180-SIL bullet in rifles?

I'm looking for a light weight to use in my .350RM and RCBS 357-180-SIL looks like it might work well because most of it appears to be bearing surface. So far I've tried SAECO 399 with poor results.

MJ

[Johnch]

I have used it in the 35 Wellen
If I keep the velosity below 2000 FPS it works fine
I can keep most loads in the 1.5 - 3 MOA

Above 2000 FPS I can't always hit the paper and I have major leading problems with some loads
But it might be I haven't found the right aloy hardness for my rifle at those velositys

I have to admit , I haven't spent a lot of time trying either

John

[Marlin Junky]

John,

Well, I just bought the last one Graf has for now so we'll see in due time how it shoots through my rifle.

What diameter do the bullet drop from your mold in WW metal? I should be OK because the .350 looks to have a .3570" to .3575" groove diameter. I'll start with HT'd WW metal at .3585"... that should be OK through the 12" twist.

MJ

P.S. I almost forgot to ask: Does your Whelen have a long throat?

[Johnch]

Mine drops .3595 to .360 depending on the alloy

And my throat is on the long side
I seat the bullets to max magizne length
It still leave a jump
But I am using a Savage 110 and the mag is longer than my old Rem 700

IMO size the bullet to the max the chamber will take
I have a .358 grove and I size my bullets .360 or .361 depending on the bullet

30,000 or so PSI sized the bullet as it enters the rifling and I get better accurcy

John

[cbrick]

Marlin Junky, this boolit should work well in a rifle. I've shot thousands of them but from revolvers. This boolit is 65% bearing surface and is .845" in length, meplat is .150" @ 42%. Mine casts right at .3587" and WW+ tin @ 190 Gr.

If your velocity goal is in the 2000 to 2100 fps range about 18 BHN WW should work well. In top end revolver loads groups opened when boolits got harder than this.

SAECO #399 is a two diameter bullet and is the least accurate boolit I've tested in the FA revolver. I had myself convinced it would work in a rifle or closed breech single shot pistol, very interesting about your lack of success rifle. hhmmm . . . . .

I will look forward to your results.

Rick

[cbrick]

Here's a comparison photo of the SAECO #399 (left) 35 Cal 180 gr two diameter boolit next to the RCBS (right) 35 Cal 180 gr silhouette boolit.

[Marlin Junky]

John,

Your Whelen sounds like mine as far as chamber dimensions are concerned, that's why I bought a M77 in .350RM which has a narrower throat that also complements the length of the magazine box. Yeah, the .350 has a short neck and a 12" twist but if things work out as I expect, I'll may rebarrel the M77 with a 14 or 16" twist .350RM barrel.

Cbrick,

When my RCBS 35-180-SIL arrives, it'll be included in a casting session along with either SAECO 399 or maybe RCBS 35-200-FN but my objective right now is accuracy at longer range without heavy recoil . If I end up casting a bunch of 35-180-SIL and 399's, I'll shoot them side by side through the .350 and post targets.

The way the .350 is throated, it looks like 35-180-SIL will seat to just below the crimp groove in order for the leading band to just touch the rifling so it doesn't look like SAECO 399 is going to be a great fit with its front band in between bore and groove diameter. If I seat 399 to touch the rifling with its groove diameter band above the grease groove, it will require too much force to chamber the round and the bullet will probably be pushed into the case. 35-180-SIL just looks like it's going to fit well and I hope it shoots as good as it looks!

MJ

[cbrick]

Marlin Junky,

In the FA I trim 357 mag brass slightly (doesn't take much) when using the RCBS 200 gr so it will crimp in the groove and still fit the cylinder. For the RCBS 180 Gr Silhouette boolit I use DW 360 brass trimmed to fit the FA chamber right to the throat and it's a bit longer than the mag brass. Depending on your rifles chamber and throat dimensions you could do the same and make it a perfect fit and still crimp in the groove.

The RCBS 180 Silhouette is the single most accurate boolit I've tested in a revolver and I have done a lot of long range revolver group and chrono testing. I think you will like this boolit.

Rick

[Marlin Junky]

Rick,

Thanks for the input. I really don't care where the crimping groove is located with respect to the case mouth as long as it's somewhere along the bullet's bearing surface. A Lee factory crimp die is all that's necessary if a crimp is needed (which is seldom when dealing with bolt guns).

BTW, do you know of anyone successfully hollow-pointing the 35-180-SIL? I'm just thinking down the road if I get a whim to use it as a hunting bullet.

MJ

[leftiye]

If you have, or know anyone who has a lathe and a collet closer , and appropriate size collet all that is necessary is to drill out cavities in the noses of the boolits with the appropriate drill size. I like to use a small center drill and make conical cavities. There are many other machines (case trimmers, etc.) using this same principle if you can't get access to a lathe. Lathe drilling in a collet should be as/more accurate than the mold cavities were cut.

[Marlin Junky]

Here's a related question:

Will hollow-pointed, heat-treated 50/50 alloy expand against relatively light resistance (a racoon)? My understanding (which may be poor) of heat treated 50/50 alloy (Pb/clip-on WW metal) is that it doesn't harden all the way to the boolit's center.

MJ

[cbrick]

From all of the metals industry reports I've read that's wrong, steel when heat treated is a surface hardening. Lead reacts the opposite and when HT it is the same hardness all the way through. The only exception that I'm aware of is surface work softening such as sizing the bands.

As for expansion it would depend entirely on your HT technique. If you heat in the oven to just below the slump point and quench you will acheive near max hardening, about 30 BHN. At this the boolit would in all probablity break apart. Water quenching from the mould should give you around 18 BHN. Your velocity will play a key role.

This is with WW and I've never tested the results using Pure and WW. Reducing the antimony percentage by diluting 50/50 Pb/WW WILL increase the hardening/time curve. Testing I've done with WW and reduced antimony indicates that final hardness wasn't changed with HT but the time to harden was increased a lot, from 3-4 days to 3+ weeks.

Here's an article that describes this.

Cast Bullet Alloy

Rick

[mattw]

I use the RCBS 180-SIL and an old LBT 180 and 200 WFN. These 3 are just incredible in the 627 and Marlin 1894 carbine. For hunting deer the LBT's are the best but for shooting plates the RCBS is the most accurate!

[ohland]

Anyone have experience with RCBS 357-180-SIL bullet in rifles? MJ

My Dad uses them in an Encore 357/44 Rifle. My 357-180-SIL casts nicely, rain of bullets, as it were...