What to do when the load your rifle loves sucks?

[Jimmy2Times]

Ok, so here's the problem. My current load is SMK 175 gr. HPBT, 43.4 gr. IMR 4064, CCI BR2 Primer, all in a Federal Case. This is running around 2600 FPS and will get me out to 1000 yards which is my absolute finite distance requirement. The problem is it doesn't group extremely well out of my rifle. I get .75" groups at best @ 100 yards and anything from 300 yds or beyond it can hold 1 MOA at best. If I reduce the powder charge to 40 or 41 grains it will shoot .5 MOA all day long at 100 yards. But with that reduction in muzzle velocity I doubt it will get out to 1000 yards. So what do you do when your rifle's pet round is an underpowered load?

BTW, the rifle is an early Savage FP10 in .308 with a 24" barrel.

Thanks, as always, for your insight.

 

[flopduster]

Re: What to do when the load your rifle loves sucks?

It would seem that there might be an upper node you haven't reached yet, I have no experience with 4064 so I do not know how close you are to max. If there is no upper node you can reach within safe pressures, maybe change primers with your pet load and see if it will tighten up as an easy first thing to try.

imo
I am no expert

 

[Jimmy2Times]

Re: What to do when the load your rifle loves sucks?

Interesting thought about the upper node. Unfortunately the max is 44 grains for this load, and I REALLY don't like to run up to the hairy edge of a max load. I know this may sound crazy, but it's true, one time I loaded a HS50 box full of max load rounds. I started to shoot them and from the very first shot my barrel would make a ringing sound like a bell. And then after a couple of shots, the breech would get tough to open. I decided not to shoot any more of those and stay away from max loads.

 

[ChadTRG42]

Re: What to do when the load your rifle loves sucks?

Actually, I am showing 45.6 as a max charge for IMR 4064. I've had good luck with 4064 in the 308 case. Typically, book max 308 Win load data is a little low. All 308's that I have done shot best over book max. I would agree, that you are proabably not to the next accuracy node. If you work it up slowly looking for pressure, you will find better accuracy. You need about another 50-100 fps, and you'll find the next sweet spot. You will most likely have a compressed load. See if you can seat the bullet out beyond the 2.80". If you can get to 2.830- 2.860, this will help some in reducing the compression.

http://data.hodgdon.com/cartridge_load.asp

 

[Grump]

Re: What to do when the load your rifle loves sucks?

The old military M118 load with a 173-grain bullet (and I believe a marginally worse BC than the current 175 SMK) had no problems at all getting to 1,000 yard (or meters, for that matter, IIRC) at as low as 2520 fps from a 22-inch barrel.

This applied down to at least 40 F., maybe even below freezing. Don't remember any data on that.

Since you don't state the velocity of your underpowered load, I can't run the numbers and predict how far into transsonic, if any, you would be at sea level.

Since virtually all of my shooting is at at least 2,000 ft elevation, I'd go for the "underpowered" load for the sake of accuracy AND barrel life. You will need to read the wind a bit better, but you will also have more usefully accurate rounds to shoot to learn that before the barrel is likely to go south.

 

[Brians708]

Re: What to do when the load your rifle loves sucks?

Jim-Squared,
Just gonna toss this out, are you using new cases each time or using form fired/ neck sized only?

I agree with the other comments as well, upper node may have not been reached, and at least in many Rem's ( don’t know about the sa-vage) I have the book values can usually be exceed prior to pressure signs.... even in which case if I have pancaked a primer on the upper and it shoots well, I stick wit it!

 

[MitchAlsup]

Re: What to do when the load your rifle loves sucks?

There should be another accuracy node around 2650 fps if you can reach it without pressure signs.

 

[FIREMEDIC27]

Re: What to do when the load your rifle loves sucks?

Try using Winchester or Federal primers. I tried virtually the same load changing only the primers. Win LR primers gave the best grouping. Say what you want, but Win primers shot .5" group and BR2 primers or standard CCI's grouped around 1.5" @ 100 yards. Oh yeah, Savage 12BVSS 308 Win, 26" barrel

 

[Queequeg]

Re: What to do when the load your rifle loves sucks?

J-Squared,

What luck with other powders? 4064 is my third choice (though IMR 4895 is getting close to supplanting it!)

I definitely have to explore this ladder business...

 

[Jimmy2Times]

Re: What to do when the load your rifle loves sucks?

OK, to answer some questions:

I am using full length resized cases each time. Initially trimmed to 2.005". They are on their second or third loading.

I have used IMR 4064 exclusively. I don't want to change too many things at once.

I've put together a 6 powder charge spread (6 different charges, 10 rds per charge) that I'm going to try. After that I will try the different primers as suggested.

I'll report back after this weekend.

Thanks for the help!

 

[Downzero]

Re: What to do when the load your rifle loves sucks?

I think you're using WAY too light a load. Most of us using Varget are within 1 grain of max (some even over a book max) to get the velocity and accuracy we desire.

I think the answer is already in this thread. When your load is accurate but underpowered, you work up to the next accuracy node.

You recognize that going up 2 grains is only 5%, right?

 

[jeffm]

Re: What to do when the load your rifle loves sucks?

There are a lot of powders that work in a 308. Try varget, 4895, 748? I am sure there are many others here who can recommend other powders.

 

[Tackleberry]

Re: What to do when the load your rifle loves sucks?

I am shooting 44.5grs Varget, Lapua brass, cciBR2 primers and 175smk's. This shoots great out of my rifle and several others as well. It has no problem getting to 1000.

 

[Jimmy2Times]

Re: What to do when the load your rifle loves sucks?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Downzero</div><div class="ubbcode-body">

You recognize that going up 2 grains is only 5%, right? </div></div>

Yeah, what's your point? Precisely what is the signifigance of that?

Do you realize that 35 is 50% of 70?

tacklebarry and Jeffm, maybe I will have to break down and try some Varget.

Thanks for the info.

 

[FNuser]

Re: What to do when the load your rifle loves sucks?

ditto to grump, velocity isn't everything. save your brass. The first time I shot black hills 168's I found out how cold my 43g rl15's were but they shot as good or better.

 

[Downzero]

Re: What to do when the load your rifle loves sucks?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: tackleberry</div><div class="ubbcode-body">I am shooting 44.5grs Varget, Lapua brass, cciBR2 primers and 175smk's. This shoots great out of my rifle and several others as well. It has no problem getting to 1000. </div></div>

See what I mean? .5 grain off of the max and he's happy with it. I shoot 44 grains of Varget and a 175 SMK, as does my friend in his gas gun.

I see no reason why 4064 won't shoot in your gun, though. Work up more. You're obviously almost there.

 

[308isgreat]

Re: What to do when the load your rifle loves sucks?

I'd go out and test your reduced loads. You never know until you try!

 

[Weaselthis]

Re: What to do when the load your rifle loves sucks?

Grump, I don't mean to step on anyone's thread here, but I gotta ask since you seem knowledgeable on the bullets....
I have 200 of the 173g ball you're talking about and they group pretty good from my 35yr old Rem700 in '06 whose throat is so long ya can't touch the lands w/o coming out of the case!...lol I've put a few thru it
I get 2640fps ave. w/ 19ES and it'll put 5 inside .773, not bench rest but m.o. milk jug. Got a big shoot coming up w/ the hunting bunch next week...milk jugs at 500-600 yds. No rests of any kind for braggin rights and $6.00 winner takes all...whooppee!

Do you happen to know what the BC of those bullets are? Can't find it any where. Got them 26yrs. ago along w/ 200+ LC 61 match brass and hate to use any more than absolutely necessary to get the ups for 500-600. Thanks in advance for any help ya might have. Take care.

 

[19Scout77]

Re: What to do when the load your rifle loves sucks?

I believe it is .496. Use your 175 (.505 BC) dope--it won't be very far off.

 

[Grump]

Re: What to do when the load your rifle loves sucks?

I'll have to defer to 19Scout77 on this.

When I shot them, I didn't have a chronograph, so my come-ups won't help. However, I remember some source(s)(?) listing it in the high .4xxs, and much better than the 168 SMK's .440 or so.

 

[Weaselthis]

Re: What to do when the load your rifle loves sucks?

thanks guys. got sidetracked on this thread and lost it. Sorry for the late come back. Preesheate the info. Take care.

 

[JLM]

Re: What to do when the load your rifle loves sucks?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MitchAlsup</div><div class="ubbcode-body">There should be another accuracy node around 2650 fps if you can reach it without pressure signs. </div></div>

Indeed. I think you should stick with it Jimmy. I'm doing well with the same rifle at 42.8gr with a Fed 210M. Its clocks right at 2640. I think you are almost there. Accuracy doesn't drop off at distance, and the vertical is better than my Varget load.