284 Shehane fireformed load development

[Caleb.E.]

Hello all,
I have a 284 Shehane built on a Rem 700 LA and a Shilen 26” rem Varmint contour barrel as a medium weight long range hunting/ target rifle. Do most of my load testing at 500 yards and achieved great accuracy fireforming with 54 gr of H4831sc and a 180 hybrid .020 off, 5 shot groups consistently under .5 MOA. However after fireforming my brass I have had a difficult time achieving that same accuracy, even with an identical load. Best 500 yard group since FF was just over 2.5” at 500, shot with 55.5 gr. However it showed some vertical and spreads were too high for extreme long range accuracy. I am aware that I am hindered with shorter barrel length from reaching the known upper nodes, and I began to see pressure signs at 57 gr with no worthwhile accuracy gain at that charge. Was wondering if anyone has experienced some of the same trials after fireforming, or had success nailing down a consistent load with similar components.

 

[Tahoe Shark]

Hello all,
I have a 284 Shehane built on a Rem 700 LA and a Shilen 26” rem Varmint contour barrel as a medium weight long range hunting/ target rifle. Do most of my load testing at 500 yards and achieved great accuracy fireforming with 54 gr of H4831sc and a 180 hybrid .020 off, 5 shot groups consistently under .5 MOA. However after fireforming my brass I have had a difficult time achieving that same accuracy, even with an identical load. Best 500 yard group since FF was just over 2.5” at 500, shot with 55.5 gr. However it showed some vertical and spreads were too high for extreme long range accuracy. I am aware that I am hindered with shorter barrel length from reaching the known upper nodes, and I began to see pressure signs at 57 gr with no worthwhile accuracy gain at that charge. Was wondering if anyone has experienced some of the same trials after fireforming, or had success nailing down a consistent load with similar components.

Perhaps I am misunderstanding but you may not have a problem at all. 2 1/2” @ 500 yd is about .5 MOA, the same as your FF group.

 

[jbpmidas]

In the Shehane I had, I had to go up in charges to find a good node. But, when I found it, it was a hammer!

 

[Caleb.E.]

Thanks jbpmidas, mind if I ask about how much you had to go up in charge?

Tahoe Shark, I know what you mean about the .5 MOA, and I would be happy if that load had shot consistently, but the vertical and velocity spreads were just too high to consider staying there and especially for pushing it out to 1000.

My 54 gr fireforming load was shooting single digit SD and 12 ES. I know the Shehane is a modest case form, however the change in pressure afterward has to alter the ballistics somewhat, or at least it has in my situation.. that load will not shoot that way for me again in a FF case. I know there has to be a sweet spot somewhere with a higher charge, just looking for any helpful input as I have struggled finding it.

 

[jbpmidas]

Been a few years, but if memory serves I added about a grain or so. 54.2 was fireform. Seems like 55.5 was low node and 56+ was high node. 180VLD jammed .010 was bullet. Lapua brass.

 

[Yote Hunter]

I’m thinking maybe you are just green behind the ears in shooting. More practice would probably decrease your group size.

 

[Yote Hunter]

Just kidding! I hunt and shoot with this guy. He’s a pretty fair shot.

 

[Rope2horns]

H4831sc 55-57gr
H4350 51-53gr

I’ve found good loads around 56.4 H4831 area and 52.5 H4350 area. This is with a .225fb.

Fire forming accuracy can be hard to duplicate because it shoots so darn small when you get it right. A full power load will shoot just as small it may take a little more work.

 

[jr600yd]

^^^^^^ +1 what they said. My F open rifle has a node 55.5 - 56.5 H-4831. Also 56 of R-26

 

[Caleb.E.]

Yote Hunter thanks for the constructive criticism.. (and the correction) haha! I know you didn’t want people thinkin you hunt with a lead slinger lol.

Thanks everyone for the positive input, time to load up some rounds and get back to testing. Think I’ll load up some .5 grain increments 55-57 and go from there.

 

[TroyG]

My Shehane load is 56.5 of H4831 with JLK 180gr VLDS at 015-020 jam. If I go to 57 bad things happen to the brass. I am leaning on mine hard and still only getting 2880 fps although barrel is quite new. I would like to try some RL 26 when I find some.

Yote Hunter thanks for the constructive criticism.. (and the correction) haha! I know you didn’t want people thinkin you hunt with a lead slinger lol.

Thanks everyone for the positive input, time to load up some rounds and get back to testing. Think I’ll load up some .5 grain increments 55-57 and go from there.

 

[ShootDots]

My Shehane load is 56.5 of H4831 with JLK 180gr VLDS at 015-020 jam. If I go to 57 bad things happen to the brass. I am leaning on mine hard and still only getting 2880 fps although barrel is quite new. I would like to try some RL 26 when I find some.

Hello Troy.. I shoot a "straight" .284 with 180 Hybrids. My load is 54.0grs of RL-23. It is sailing along at 2910 with NO pressure signs! Brass has lasted with tight primer pockets for several loadings now! I have never tried it in my .284 BUT it is my understanding that you can get "unreal" velocities with RL-26.

 

[Pappy42]

My Shehane likes 56.5-56.7 of H4831 and Berger 180VLDs at just touching the lands. Out of my 30 inch barrel, it runs an average of 2830fps.

 

[Zero333]

You can try to chase the same velocity of the FF loads... but usually FF loads are slower.

 

[TroyG]

Hello Troy.. I shoot a "straight" .284 with 180 Hybrids. My load is 54.0grs of RL-23. It is sailing along at 2910 with NO pressure signs! Brass has lasted with tight primer pockets for several loadings now! I have never tried it in my .284 BUT it is my understanding that you can get "unreal" velocities with RL-26.

Maybe I have a faster lot of H4831? I never tried another powder. Found a good load with low SD and ES that shot well. In the past I have used too much valuable barrel life trying too many different load variables.

 

[ShootDots]

Maybe I have a faster lot of H4831? I never tried another powder. Found a good load with low SD and ES that shot well. In the past I have used too much valuable barrel life trying too many different load variables.

RL-23 is about "a shade" faster than H4831SC in my experience. However, it produces considerably more velocity for the same pressures. 54.0grs +/- is where it is at for the "straight" .284 with RL-23. If you can reach .284 Shehane / Walker velocities sans the fireforming, it becomes a win-win situation.

 

[1shot]

RL-23 is about "a shade" faster than H4831SC in my experience. However, it produces considerably more velocity for the same pressures. 54.0grs +/- is where it is at for the "straight" .284 with RL-23. If you can reach .284 Shehane / Walker velocities sans the fireforming, it becomes a win-win situation.

^^^^^^^
What Ben said!