Tuning a Hammer Load

gltaylor

gltaylor

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There has been a lot of conversation about "tuning" Hammer loads over the last few years. How to do it and what benefits can you expect?
Well, I finished "tuning" the load I'm going to hunt with for my new toy today. I thought this might provide a really graphic example of the (my) final tuning steps when a new load is developed for a new bullet in one of my rifles.

Obviously, the initial tuning is done in the powder charge used to get the best overall groups. I also want the best case fill % and the most velocity. My target (desired) case fill % is around 90%This frequently takes me at least 3 powder trials. Many of my cartridges are wildcats, so there is no basic load data to follow. For other standard cartridges, it is very simple to look at our posted data for reference (THANK YOU ALL FOR SHARING!!!).

Once the best powder charge is selected, the final step I've been using is trying different crimp settings. I always start with 1/8T FCD crimp when doing powder charge tests. If the load is developed with a crimp initially, adding more crimp does not appear to materially affect either speed or pressure.

Once the powder charge is dialed in, I change crimp settings in 1/8th turn increments and shoot groups. Usually, a specific setting will outperform the rest. That was the case again today. The rifle was shooting approximately .06-.07" groups prior to the test. I'll post the progression of the tests below. This is the first time I've had a crimp setting this high win out! (that's just for you, @joe16). Usually I get best results at 1/8 to 2/8 turns. Not this time.

I'll take a .239 100 yd. group ANY DAY. This was with the 123 Absolute Hammer at 3810 fps, 100 yds., in the 26 Sherman Magnum. Next is confirming drops to 400 yds (my maximum hunting shot distance).

The group sizes, left to right, are .555, .461 and .239!

Enjoy!
 

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Thanks @gltaylor for sharing how you tune your final hunting loads. When you say your desired case fill is around 90%, what exactly does that mean? 90% of powder filled all the way to the top? 90% of powder filled to the shoulder/neck junction? Something else? Do you want to be able to hear some powder rattle back and forth once you seat a bullet and shake it?
 
Great info just in time as Im learning how to fine tune my Hammer loads.
Using the 1/8 turn increment; What is the most crimp turns that can be used?
 
DiscoSteve said:
Thanks @gltaylor for sharing how you tune your final hunting loads. When you say your desired case fill is around 90%, what exactly does that mean? 90% of powder filled all the way to the top? 90% of powder filled to the shoulder/neck junction? Something else? Do you want to be able to hear some powder rattle back and forth once you seat a bullet and shake it?
Click to expand...
Good question! Sorry I wasn't clear.
I prefer powder to be up to the case shoulder if possible. Above is fine. Lightly compressed is fine. I rarely can hear powder "rattle".
Take your case (with primer in) and fill it to the top with the powder you're using. Dump that and weigh it. Take about 90% of that weight. That's the target I'm hoping for.
Most of my best loads are at or just barely below the case shoulder (where the straight walls meet the shoulder).
Does that help?
 
Koda said:
Great info just in time as Im learning how to fine tune my Hammer loads.
Using the 1/8 turn increment; What is the most crimp turns that can be used?
Click to expand...
I have no idea. Butterbean may answer that question?
The most I've personally ever used is 1/2 turn (4/8 turns). Some go straight to 4/8 and leave it there? My loads vary because I test each setting for best accuracy (1/8, 2/8, 3/8 & 4/8.
 
Koda said:
Great info just in time as Im learning how to fine tune my Hammer loads.
Using the 1/8 turn increment; What is the most crimp turns that can be used?
Click to expand...
You can turn it until it cuts the bullet in half if you want to, there's no limit on how light or heavy, it's a tuning tool so it's up to you.
I will say it makes me smile that GL in particular and tons of other folks have come to appreciate the value of this tool,
 
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ButterBean said:
You can turn it until it cuts the bullet in half if you want to, there's no limit on how light or heavy, it's a tuning tool so it's up to you.
I will say it makes me smile that GL in particular and tons of other folks have come to appreciate the value of this tool,
Click to expand...
Hi Mr Bean,
Between yourself and Farleg, for the first time in forty years l am about to spend $ on some Lee FCD's, especially for my Beanmore, but I also think it can't hurt to test on the rest of my rifles, l don't know if you guys realise how much money and how far down the rabbit hole l am going ( l have followed you for a number of years on another site) But it's a lot of fun,
And learning.
Regards
🐢
 
Turtle566 said:
Hi Mr Bean,
Between yourself and Farleg, for the first time in forty years l am about to spend $ on some Lee FCD's, especially for my Beanmore, but I also think it can't hurt to test on the rest of my rifles, l don't know if you guys realise how much money and how far down the rabbit hole l am going ( l have followed you for a number of years on another site) But it's a lot of fun,
And learning.
Regards
🐢
Click to expand...
That rabbit hole only gets deeper. But it's worth every dollar.
 
Turtle566 said:
Hi Mr Bean,
Between yourself and Farleg, for the first time in forty years l am about to spend $ on some Lee FCD's, especially for my Beanmore, but I also think it can't hurt to test on the rest of my rifles, l don't know if you guys realise how much money and how far down the rabbit hole l am going ( l have followed you for a number of years on another site) But it's a lot of fun,
And learning.
Regards
🐢
Click to expand...
The FCD helps everything, not just Hammers
 
Crimping? I was using Hammer Bullets from the beginning of Hammer Bullets for three or four years before I even heard of crimping a rifle bullet.

I know I excel at ignorance, but can't say it out loud. If I do the Executive V.P. comes unglued.
 
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