110BA 300 Scenars and SMKs

[jfields]

I was wondering if any of you gents could compare your findings with mine as they relate to H2O case capacity, chamber length and barrel length for my new 110BA in .338LM. I really don't have anything to compare on chamber or barrel length. I will use the method described above when I get home tonight to measure OAL for the Scenars and SMKs. I tried to measure the barrel, but it was a little difficult without removing the brake. Is the barrel exactly 26 inches? I have loaded to 3.690 previously with no problems, but am seeing pressure signs at 3.700. Am I jammed in to the lands?

I have measured 10 of my fired cases and come up with a water capacity of 116 grains. That has me a little concerned as the default in Quickload is 108.

The very first shot this morning resulted in a very stiff bolt and a stuck case. The load was almost exactly 60,000 PSI as per QL. I have done a fair amount of shooting right at max pressure and not had this problem before. Needless to say I will be backing off quite a bit.

The test load was with a 300 Scenar and 95 gr. of Retumbo at 3.700 OAL. I had worked up to 96 grains with the SMKs previously and QL showed only slightly more pressure with the Scenars.

Any help will be greatly appreciated.

Thanks,

Shaky

 

[ChrisGarrett]

Re: 110BA 300 Scenars and SMKs

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Shaky97</div><div class="ubbcode-body">I was wondering if any of you gents could compare your findings with mine as they relate to H2O case capacity, chamber length and barrel length for my new 110BA in .338LM. I really don't have anything to compare on chamber or barrel length. I will use the method described above when I get home tonight to measure OAL for the Scenars and SMKs. I tried to measure the barrel, but it was a little difficult without removing the brake. Is the barrel exactly 26 inches? I have loaded to 3.690 previously with no problems, but am seeing pressure signs at 3.700. Am I jammed in to the lands?

I have measured 10 of my fired cases and come up with a water capacity of 116 grains. That has me a little concerned as the default in Quickload is 108.

The very first shot this morning resulted in a very stiff bolt and a stuck case. The load was almost exactly 60,000 PSI as per QL. I have done a fair amount of shooting right at max pressure and not had this problem before. Needless to say I will be backing off quite a bit.

The test load was with a 300 Scenar and 95 gr. of Retumbo at 3.700 OAL. I had worked up to 96 grains with the SMKs previously and QL showed only slightly more pressure with the Scenars.

Any help will be greatly appreciated.

Thanks,

Shaky </div></div>

First of all, Quickload is only a 'guide'--a comprehensive guide, but nevertheless, only a guide and not the 'word of God'.

Secondly, you'll decide what constitutes 'too much pressure' for your particular ammo combo and your particular weapon.

All chambers are going to differ, unless they were cut with the same exact reamer in the same exact manner--at least for the first X amount in a batch, or until the reamer starts wearing out.

3.690" for a 300gr bullet seems a bit generous in the throat, but I pretty much stick with the 250s, as my Sako is a 1:12" twist, so I can't say if that's a conservative OAL, or not.

You might just invest in the Hornady/SP modified OAL cases and tool, to let you know for sure, where your lands are at with any given bullet.

What are the pressure signs you're getting at 3.700" that you're not getting at 3.690"? That what temps are you shooting at?

In my Sierra V manual, using the 250 SMK, max for Retumbo is listed at 94.6gr, so I'm thinking that a 300gr SMK/Scenar will be a lower charge than that, so 96gr of Retumbo might be too much.

Remember, however, Sierra is a conservate manual.

AmmoGuide has the 338LM case estimated at 111.8gr of H20.

Chris

 

[jfields]

Re: 110BA 300 Scenars and SMKs

Thanks, Chris.

The pressure signs I had this morning were a very stiff bolt and a stuck case. I am sure the primer is flattened, but have not gotten the darn case out of the chamber yet. It was a quick range trip between meetings and I forgot my cleaning rod. I ran Retumbo up to 96 grains at 3.690 last weekend. The bolt started getting heavy at 96, so that is where I stopped. That was with the SMKs, today I was shooting Scenars at 3.700. I will measure the OAL with the the cleaning rod/rod stop method this evening.

Thanks for you input.

-Shaky

 

[ChrisGarrett]

Re: 110BA 300 Scenars and SMKs

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Shaky97</div><div class="ubbcode-body">Thanks, Chris.

The pressure signs I had this morning were a very stiff bolt and a stuck case. I am sure the primer is flattened, but have not gotten the darn case out of the chamber yet. It was a quick range trip between meetings and I forgot my cleaning rod. I ran Retumbo up to 96 grains at 3.690 last weekend. The bolt started getting heavy at 96, so that is where I stopped. That was with the SMKs, today I was shooting Scenars at 3.700. I will measure the OAL with the the cleaning rod/rod stop method this evening.

Thanks for you input.

-Shaky </div></div>

Yeah, definitely sounds like some pressure issues, but Savage has reamed some funky chambers on the 338LM, since the introduction of the 110BA, a couple of years back.

The problem seems(ed) to manifest itself mostly with Hornady brass and the issue of that brass sticking in the chamber and not extracting easily enough.

Anyhow, try a different powder, as well. Use the dummy method to find the lands, but look into the Hornady COAL gage and cases. They work pretty well.

SMKs can stand a jump and are pretty forgiving making that jump, so you don't need to jam the lands with them, which can only spike pressures.

Chris