.284 Shehane and H1000

[ShootDots]

Several months ago, when I got my first .284 Shehane, I tried H1000 with the Berger 180 Hybrids. I got very good accuracy and excellent velocity, however, the E.S.'s were "about" 40f.p.s. No matter what I tried I could not get the E.S.'s lowered. The powder was just a shade too slow. It would simply not burn efficiently enough to get good E.S.'s..

With H4831 and IMR 7828 I am doing right at 2900F.P.S. with E.S.'s down under 10F.P.S. GREAT RIGHT? Yes and no. I am slowly opening up primer pockets. Well, I was tired of "prepping" 180 Hybrids so I decided to try the Lapua 180 Scenar "L".. To make a long story short, the Scenars are "already prepped" so to speak and I easily developed a load with both H4831 and IMR 7828. However, the bearing surface on the Scenars is CONSIDERABLY longer than the Hybrids and I had to drop the charges nearly a grain to attain the same speed and accuracy. BUT the primer pockets are still slowly opening up. So I thought, "those Scenars, with the MUCH LONGER bearing surface MAY (hopefully) allow me to use H1000". That should slow the progress of the primer pockets loosening up considerably.
So I decided to revisit H1000 using the 180 Scenars.

Well, at 300 yards it is APPEARING to accomplish what I want. I am getting 2900f.p.s. with 11ft. E.S.'s. I am getting nearly 3/4" to right at 1" for 5 shots at 300 yards. So now to REALLY give them the "test".. Next week I will take it out to 1000 yards and shoot 6 groups of 5 shots each.. I will not shoot for "X"'s, I will shoot for groups. If I can equal what I am doing with either H4831 or IMR 7828, I will be in business! If this works, and I believe it will, this will be the answer to the problem of the primer pockets loosening up as pressures will be W-A-Y down...

We shall see... Once I shoot at 1000, I will bring the results back here..

 

[Jeffvn]

Thanks for the update. I know several shooters (including my brother) using Improved forms of the .284 that have similar results to yours.

Jeffvn

 

[bsumoba]

good info! for me also since I have a 284 Shehane in development right now.

What barrel length do you have?

I have a 284 Shehane and during my initial development, I was getting about 2900 fps with H4831SC and 180gr hybrids with very good accuracy, but its on the high side of the charge weight. I was getting very faint swiping and no other sign of pressure really. I only have 2 firings on the brass, but pockets are still very tight on my lapua brass with that charge weight.

I have another charge weight which is backed off and is about 56.3-56.5 gr H4831SC and it is looking very promising as well. 0.10" thou jumped and about 2860 fps with the 180hybrids. On the slow side, but my barrel only has 120 rounds through it. I am going to be extending my FB out to about 0.210-0.215 (currently 0.188") as well so I stopped load development to wait for my unithroater to come in. This might/should help get less pressure when I seat the bullet out farther than what I am doing now and allow me to develop that 57-57.2 gr load so I can be around that 2900 fps range that I want to be in with a 30" barrel with no donut issues affecting my neck tension.

My initial ES was horrible (20-25 ES), but I had less than ideal light conditions for my cheapo chrono as I was also getting error readings and flyer numbers like 2200 fps every 4 shots or so even though the groups were sub-3/8" in most cases. No obvious flyers in the group as they all grouped well. Need/Should invest in a better chrono I'm thinking or simply shoot in more shaded/overcast conditions...

 

[Elwood]

Benjamin, I'm interested in what your free bore is? As I understand it the Scenar needs at least .250 plus.

 

[ShootDots]

To answer both questions:

bsumoba:
1.) I have a 31" Barrel..

Elwood:
2.) I HAD a .220 freebore. However, I now think it is somewhere NORTH of .250 due to 600+ rounds down the bore. I think you need, at a minimum, for the 180Scenar, a .250 and a .275 might be better yet..

 

[Erik Cortina]

To answer both questions:

bsumoba:
1.) I have a 31" Barrel..

Elwood:
2.) I HAD a .220 freebore. However, I now think it is somewhere NORTH of .250 due to 600+ rounds down the bore. I think you need, at a minimum, for the 180Scenar, a .250 and a .275 might be better yet..

Ben, I find it really hard that you would have .030" of erosion in 600 rounds. It's usually ~.001 - .003" per hundred.

 

[ShootDots]

That may be Erik... I do know this, that L-O-N-G Scenar barely is above the neck shoulder junction with the bullets seated 3K off the lands.. The Scenars have, as close as I have the ability to measure them, 68K MORE bearing surface than the Hybrids. My Hybrids seat nearly 1/2 the way up my neck.. So all I am doing is guessing as to how far my erosion has forwarded my freebore.. But it is only a guess..

 

[ShootDots]

I needed to fireform some new brass, as the brass that I was shooting was getting on in age.. So today I went out to fireform 30 pieces that I will be testing at 1000 some time next week and all I can say is WOW! I was shooting the discontinued Berger 175 XLD's jammed 15K into the lands. I was using 57.5grs of H1000 (1 FULL grain lower than the load I will be trying out at 1000). I did not chrono them as all they were, were fireforming rounds. Well after the barrel "fouled out" (right at 10 shots) I shot 4 groups of 5 shots at 300 yards. The largest was 1.5, most "hovered" just at an inch or slightly over and 1 had 4 shots UNDER 1/2".. The "5th" shot (which was actually the 3rd shot) I bumped my 2oz trigger when I did not want to and the rifle was NOT where I would have pulled the trigger and I got "bumped" in my forehead. Even with the "called bad shot" that lone shot was only 1 inch from the tight little cluster. There is NO DOUBT in my mind that had I not messed up, I would have got a group somewhere SOUTH of 3/4" and maybe less than the 1/2" mark! Those 175 XLD's ( I only have 40 left) shot awesome! The nice benefit if it was that the primer pockets are still like brand new! Exactly what I had hoped for>>> Now lets see what transpires at 1000 nest week with the 180 Scenars..

 

[ShootDots]

Re: .284 Shehane and H1000 ****UPDATE****

****UPDATE****

Well as promised, I took the Shehane out to 1000 yards to see how it would do.. ALL the loads were the same, however, I did change one component. I shot MOST (20 shots / (4) 5 shot groups) with the Wolf L/R primer and (2) 5 shot groups with the Fed 210GM's. The Wolf primers shot with a 4-5" vertical and the Fed 210's shot with a 9" vertical.. So, needless to say, I will use the Wolf primers. It shot just as well as the H4831 OR IMR 7828 with the benefit of TONS less pressure. I do not believe I will face the "short primer pocket life" syndrome anymore!

 

[brxbrad]

I wonder what the results would be with H4831SC. I have a .284 Win and have had great results. I have a 32" Bartlien and also shoot 180 Bergers. Velocity running 2830 at 54.5 gns with 9 ES. I've shot about 1900 rounds through it using the same 100 pieces of Lapua Brass and haven't had any problems primer problems. I'm considering a Shehane build and would appreciate any feedback.

Thanks
Brad

 

[ShootDots]

I have loads with H4831SC for BOTH the Berger 180 Hybrid and the 180 Scenar. The Hybrid load is 57.0gr H4831SC, seated 22K OFF the lands and Fed210GM primers. Velocity 2910 with e.s. under 10, usually about 6-8f.p.s. The 180 Scenars have a load of 56.2grs. of H4831SC, seated 2-3K OFF the lands with Fed210GM primers. It shoots exactly like the Hybrids without all the "bullet prep".. I hope this helps..

 

[Blaster-37]

I have loads with H4831SC for BOTH the Berger 180 Hybrid and the 180 Scenar. The Hybrid load is 57.0gr H4831SC, seated 22K OFF the lands and Fed210GM primers. Velocity 2910 with e.s. under 10, usually about 6-8f.p.s. The 180 Scenars have a load of 56.2grs. of H4831SC, seated 2-3K OFF the lands with Fed210GM primers. It shoots exactly like the Hybrids without all the "bullet prep".. I hope this helps..

Have you experimented with jumping the Lapuas?
greg

 

[ShootDots]

No I have not... The reason: I have a .220freebore + wear and the Sceanrs have such a L-O-N-G bearing surface that keeping them as close to the lands as possible BARELY keeps the shank out of the neck. I tried going into the lands and that was TERRIBLE!