New build for ELR hunting. .300 BSM (30-416 Rigby)

[NEMTHunter]

Howdy,

Been working on .308 cal project for the 245 bergers (when they get here

) since early this year and parts just kept slowly trickling in. Last part was the barrel. Had to wait almost seven month for it. To be sure it was hard waiting but I am sure its going to be worth it! As soon as the barrel showed up it got sent of to the smith for reaming, threading the shank and muzzle along with a crown job. Got the parts back and put it all together. Have 20 shots through it so far and it's looking very promising.

To date I have seen 3284fps with H50BMG powder and fed primers shooting the 230 OTM berger. Still have room to go up in charge weight. No real signs of pressure. Started @ 105 grains and ran it all the way to 120 and the primers still look the same. no ejector marks or remotely stiff bolt lift.

A little info on the cartridge. I call it the .300 BSM (Big Sky Magnum) Its a 416 Rigby necked down to 30 cal. and blown out. I will say this it bears no resemblance of the .416 other then the head stamp. Its a new design I did not go with the 40 degree Ross style reamer.

The rifle started out as a Savage 112 Magnum Target chambered in .338 Lapua. Below are eh specs as of now.

Action: Savage 112 Magnum Target.

Trigger: Factory Savage set to 1.5 pounds. Its very nice for a factory trigger.

Stock: Factory Savage 112 stock.

Barrel: Bartlein SS, 5R, 32" Finish twist of 7.5", Strait tapper after 6 inches to .875 at muzzle.

Scope: SWFA 3-15x42 SFP MOA

Scope base: 40 MOA EGW HD

Bipod: Atles clone from over the big blue sea. Its rail mounted.

Brake: Factory savage. I do plan to get a better one in the future. Might as well use the one I have for now.

I also installed a 3" picatinny rail on the forearm to mount the Bipod and sling.

Now for a couple pictures....

Left to right: 30-06/215 berger, .300 BSM/230 Berger OTM, .300 BSM/ 230 SMK and once fired .300 BSM

Same as above just a areal view of the hollow points.. The 230smk does not have much of a hole. If you could even call it that.

 

[sable tireur]

Some historical background from another author (not me):

In his article in the September, 1991 issue of GUNS & AMMO ("Hits at a Half-Mile--And Beyond"), Ross Seyfried said that his .30 Cody Express (which he called a ".30-416 Rigby Ackley Improved") preferred WC872 powder.
Ross' rifle was a Ultra Light Arms (!) single shot chambered for .30/416 Rigby necked down and blown out.

The rifle had a Douglas barrel.

He used .50BMG powders getting 3500fps with 200-220gr bullets.

Ross Seyfried's ultra long range rifle cal: 30/416 Rigby imp.

The rifle has a prototype Ultra Light Arms 40 single shot action, 34" Douglas stainless .30cal BR barrel with 1-10" twist, straight (no taper) 1.4" thick. Kevlar light BR-type stock painted as the US flag. The rifle was topped by a Leupold M4-16X.

Ross made cases using Norma 416 Rigby brass necked down in 4 steps and fireformed to a 40 deg. shoulder.

Ross fired 200gr and 220gr Sierra MK's with at the time, 1991, alvailable and "unalvailable" .50BMG powders.

Some data:

200gr Sierra MK, 116gr H5010/MV=3550fps, 127gr WC872/MV=3650fps.

220gr Sierra MK, 124gr WC872/MV=3470fps.

Huntingtons lists dies for a .30-416 Rigby 40 degree imp (Ross Seyfried)

 

[NEMTHunter]

The only thing the 30 Cody express and the .300 BSM share is the .416 Rigby as the parent case and a bullet diameter of .308.

Still I have read about the 30 Cody Express for the past year or more and it intrigues me. It just did not have the capacity I wanted.

 

[NEMTHunter]

Just got the 230SMK to 3367 fps with H50BMG powder. The load was a stiff load. I will not be going higher then that with H50BMG. I will be backing off a little and keep it around 3300.

Also got the 230 berger OTM to 3341. No plans to go hotter. Backing off a little.

Nice thing is it did not fly apart at 3367 and a 7.5 twist. Made nice little round holes @102 yards!

I am going to try same US869 and see how it does.

 

[can1010]

the couple of times I needed powders that slow I had better luck with RL-50 than I did with US869 for temp spikes. also herd that H-50 BMG was being discontinued but that can just be internet BS not quite sure. RL-50 also gave the best velocity.

 

[NEMTHunter]

Thanks for the tip. I have a jug of US869 so I will be testing it. BUT have heard what you said about the temp stability, Or the lack of it.

You are right about H50BMG powder. Its discontinued. Sad but true.

Was the RL50 faster then US869 or H50BMG? I would love to test some WC872 powder. Just have not been able to find it as new powder. Pull down only.

 

[can1010]

RL-50 was about 20-30 fps faster than H50BMG and had better case fill. gave up on US869 when blew primers in a 20 degree temp change from one weekend to the next trying to do load work up and after a little research flushed the rest of the pound down the toilet. don't remember velocity as didn't save the info.

 

[NEMTHunter]

Sounds good. Thanks for the information. I will have to look into the RL50 then. How temp stable have found the RL50 to be compared to H50BMG??

 

[can1010]

in the temps I worked in 25-70 degrees it was not a problem it was close to H50BMG but RL powders are known to get funny once you get above 80-85 degrees.
how is that savage action holding up? I am looking to build something on the 338 raptor brass from Bertram which is basically a 3 inch long lapua case maybe something close to yours for the 30 cal. heavies

 

[NEMTHunter]

Ok got you. I would like to give RL50 a try.

So far so good. Only 25 shots through it. I have heard Hornady brass is not good for high pressure loads. But so far no trouble. Even with 122 grains of H50BMG behind the 230 smk. All I got was flat primers. No stiff bolt lift and no real noticeable ejector smear. Either way I do not plan to go higher. AND after all the brass is once fired I will start over a little lower again just to be safe.

As for the Raptor brass you will have more capacity then my brass. along with better brass. IF I would have known it was in the states I would have gone that route instead.

 

[Gord0]

Maybe some VihtaVuori 20N29 if you're able to find some? It's supposed to be slower than US869.

 

[Joel Russo]

I've been shooting the .30-.416 Improved with 35* shoulder for many years... my go to powder is a VV 24N29..and the 240 SMK. I have a significant amount of WC872 powder if you're looking for some.

 

[NEMTHunter]

I've been shooting the .30-.416 Improved with 35* shoulder for many years... my go to powder is a VV 24N29..and the 240 SMK. I have a significant amount of WC872 powder if you're looking for some.

Do you know where the 24n29 falls in burn rate? I cant seem to find any information on the powder. Or even find it. They have a 24n41 powder? Is the WC872 new never loaded or is it pulldown?

How has the 30-416 worked out for you?

Maybe some VihtaVuori 20N29 if you're able to find some? It's supposed to be slower than US869.

The problem is I can only get it in eight pound jugs. If I could get it a one pound jugs I would be trying it. 225.00 just to test it is a lot to me. But I agree, I think its a good option.

Also looking to maybe try Ramshot LRT powder.

 

[Gord0]

Do you know where the 24n29 falls in burn rate? I cant seem to find any information on the powder. Or even find it. They have a 24n41 powder? Is the WC872 new never loaded or is it pulldown?

How has the 30-416 worked out for you?



The problem is I can only get it in eight pound jugs. If I could get it a one pound jugs I would be trying it. 225.00 just to test it is a lot to me. But I agree, I think its a good option.

Also looking to maybe try Ramshot LRT powder.

Ouch. I don't like to potentially toss 30ish dollars to test a pound, so I get it.