Is my load fast enough?

[weissensteinburg]

I just started reloading and am trying to make a .223 load that will get me our to 600 yards accurately. The only suitable powder I was able to find locally was IMR-4895 and I'm using 69gr SMK bullets with LC brass. The rifle is a Mossberg MVP, 18" 1:9 barrel.

I worked loads from 22.5 to 24.5 (suggested starting is 22.5, max is 25) and found my best accuracy at 24.5. My issue is that the velocity was only 2646fps and I'm a little apprehensive if that will get me the kind of consistency I want. According to the ballistics calculator I used, it will go transonic at around 690 yards. I know it's the transition that really messes things up, but is 1236 fps (at 600 yards) fast enough to avoid the effects?

 

[jwrowland77]

Yeah, but the wind between 0 and 600 are going to have more affect.

Me personally would try a different powder. My 600yd load using a 175gr SMK is giving me almost 2700fps.

 

[weissensteinburg]

I want to, but can't pony up for the hazmat fee of buying online or justify driving to another city. In the next few weeks I should be going out of town and there's a reloading store pretty close to where I'm going.

 

[MtnCreek]

4895 is a great powder for 69gr smk's. If it's shooting good at 24.5, keep going in ~0.2gr increments till you find max for your rifle. Another bullet you may want to try is Hornady 75gr HPBT.

 

[Belmont148]

Going through the same thing myself with 75 HPBT. I am using CFE223, and just couldn't get it without loosing accuracy for long range. I am about to try the same bullet with Varget to see if I get better results. Heard good things about Varget with heavy bullets and long range.

 

[MtnCreek]

Belmont, same problem here w/ cfe/75gr hpbt. I ran through workup fast and could have possibly skipped over a better load. I'm working up the same bullet w/ tac now. If you can find 8208, I've had great results with it for 75/77gr bullets in a few rifles.

 

[weissensteinburg]

4895 is a great powder for 69gr smk's. If it's shooting good at 24.5, keep going in ~0.2gr increments till you find max for your rifle. Another bullet you may want to try is Hornady 75gr HPBT.

Max for my rifle would be when I start to see evidence of case failure?

 

[Laphroaig]

When I use IMR-4895 with 69 MK's I use even a little bit less than 24.5. Remember your shooting those out of an 18" barrel. Personally I wouldn't go more than the book max of 25 and would probably settle on the most accurate, as you have so far. If it isn't too windy they will probably do fine at 600.

I have to agree with post #2 that your biggest problem shooting 69's is going to be with the wind. I don't think an extra 100 or 200 fps will change that significantly. Your 1:9 twist is going to limit using heavier bullets. I'd give 77 MK's a try, but you might not be able to stabilize them. I've tried 4895 with heavier bullets and had a few pierced primers, so I now use Varget with better results.

Laphroaig

 

[MtnCreek]

Max for my rifle would be when I start to see evidence of case failure?

You need to stop before you get there.

Read in your manual about pressure and reading pressure signs. You're shooting a bolt action, so one indication is when you start to get slightly more resistance on raising the bolt. I'm not familiar with your rifle, but assuming it has and ejector in the bolt face, looking for slight smug on the case head from the ejector is another. If you have any pronounced mark from the ejector, you've gone too far. Also, look at the edge of the primer cup; does it have a round radius or is it starting to get more of a square shape at the edge.

But,,,,,

The comment above this one about staying within published data is sound advice.

You still need to know how to identify high pressure signs, because you can get over pressure within published data. You may also find a good shooting load slightly above published data that is accurate and not too hard on your brass. The manuals do not always agree with each other. For instance, I have a .223 load that's a good bit beyond max per the bullet manufacturer and right at max per the powder manufacturer. I have a 6.5 creedmoor load that way beyond the powder manufacturer's max. I have a 300wm load that's near maxed out well below the powder manufacturer's max. If I were to jump right on the max charge I would likely need a hammer (or gunsmith) to aid in extraction. :-(

 

[weissensteinburg]

Good advice, thanks guys. I inspect brass for obvious signs of failure, but need to become more familiar with the more subtle ones like you describe. I'm going to test these loads at 300 yards this weekend and see how they do.