Heaviest 25 cal bullet we could make

[RockyMtnMT]

We got a request from a customer to make a non-expanding bullet for his 25cal to use for hunting coyotes. So we set out to make the heaviest bullet that we could that would stabilize in a 10" twist at sea level. We wanted the bullet to have a decent form for bc, so it is pointed. Just getting the bullet over 100g was difficult. Turns out that it is not possible to add weight by lengthening the shank of the bullet without sacrificing stability. In other words it gains in length faster than it gains in weight. So in the end the only place that the bullet could gain weight to increase stability was to add it in the nose. But if the nose gets too blunt then the bullet looses any bc that is gained by the added weight.

So for your guys that are waiting for a high bc 25cal bullet to shoot in your factory 10" twist rifles.....don't hold your breathe. Tried all day to beat physics and it still is not possible.

Here is a pic of the 105g Target Hammer. I like how it turned out should shoot very well. Would expect it to be able to run about 3400fps in a 25-06 with an estimated G7-BC of .226. At 3000' elevation this would stay supersonic to 1400y. Should be fun.



Steve

 

[MudRunner2005]

That's cool Steve. What do you think a HP version would weigh? 100?

 

[RockyMtnMT]

We have one already that is designed for 9.5" twist at sea level. We call it the Heavy Hammer and it came in at 104g. It is 1.145" compared to the Target Hammer at 1.138". The Target Hammer actually needs 9.75" twist to get to 1.5sg at sea level. I really am not too worried about stability in the target bullet since it does not have much of a job after impact. The 104g Heavy Hammer we designed for 257 Weatherby. Sent a bunch to family in MS for their deer season last month. Bullet performed very well.

It still amazes me how the 25cal got saddled with such a slow twist. I have checked stability on many other 25cal bullets and most of them are quite marginal.

So if you have a bit of elevation the 104g Heavy Hammer will probably work well in your 10" twist. 3300fps in a 25-06 should be achievable.

Steve

 

[just country]

morning, 110gr Nosler Accu-Bond is a very good bullet. I shoot this in my

257STW. 100g. Barnes TTSX is a very good bullet. THK. U lightbulbgun)

 

[MudRunner2005]

We have one already that is designed for 9.5" twist at sea level. We call it the Heavy Hammer and it came in at 104g. It is 1.145" compared to the Target Hammer at 1.138". The Target Hammer actually needs 9.75" twist to get to 1.5sg at sea level. I really am not too worried about stability in the target bullet since it does not have much of a job after impact. The 104g Heavy Hammer we designed for 257 Weatherby. Sent a bunch to family in MS for their deer season last month. Bullet performed very well.

It still amazes me how the 25cal got saddled with such a slow twist. I have checked stability on many other 25cal bullets and most of them are quite marginal.

So if you have a bit of elevation the 104g Heavy Hammer will probably work well in your 10" twist. 3300fps in a 25-06 should be achievable.

Steve

Yeah, I'm at around 500' ASL right now. So it might work. And only a 104gr bullet, I should be getting more than 3,300 fps out of my 26" .25-06 AI. It's only about 50-100 fps slower than my old.257 Wby which was around 3,400-3,450 with a 110 NAB. Hmmmmm...

 

[RockyMtnMT]

I would have to go look back but I think we were getting pretty close to 3600fps in the Weatherby with the 104g. Super flat. Makes milkshakes out of the insides of deer.

Steve

 

[86alaskan]

so, suppose someone had the foresight to have their new custom barrel 25-06 cut rifled at 1-9". What kind of stability would one expect at around 500' ASL? I can run 115 berger at over 3100 pretty easy from that barrel at 24". Also, is the target hammer hollow point? can it be used to hunt given the faster 1-9" twist?

 

[RockyMtnMT]

so, suppose someone had the foresight to have their new custom barrel 25-06 cut rifled at 1-9". What kind of stability would one expect at around 500' ASL? I can run 115 berger at over 3100 pretty easy from that barrel at 24". Also, is the target hammer hollow point? can it be used to hunt given the faster 1-9" twist?

The Target Hammer is not an hp. It will not expand for hunting. The customer that requested it specifically did not want the bullet to expand for coyote hunting. I would use our Hammer Hunter for coyote but he wanted the smallest holes possible.

9" twist would handle all of our Hammers other than the 128g that we designed for 1-7" twist. We have not designed one for an 8" twist yet, but I am sure that we will. We have a 7" twist test rifle coming soon.

I think the 25cal deserves an 8" twist or faster to really make it a longer range contender. Or just to use some heavier bullets well.

Steve

 

[9ptbuk]

We have one already that is designed for 9.5" twist at sea level. We call it the Heavy Hammer and it came in at 104g. It is 1.145" compared to the Target Hammer at 1.138". The Target Hammer actually needs 9.75" twist to get to 1.5sg at sea level. I really am not too worried about stability in the target bullet since it does not have much of a job after impact. The 104g Heavy Hammer we designed for 257 Weatherby. Sent a bunch to family in MS for their deer season last month. Bullet performed very well.

It still amazes me how the 25cal got saddled with such a slow twist. I have checked stability on many other 25cal bullets and most of them are quite marginal.

So if you have a bit of elevation the 104g Heavy Hammer will probably work well in your 10" twist. 3300fps in a 25-06 should be achievable.

Steve

Steve, I've followed with interest this thread about your bullets, I've owned 4 different 25-06 factory rifles through the years and am currently shooting a LR700 Remington . EVERY one of my rifles preferred the shorter bullets ( Example: Sierra 100gr Pro Hunter ) and shorter . I understand the 10" twist in my barrel is probably the problem, But am wondering why some have rifles that do well with the longer bullets with the 10" twist ??? Also, What bullet do you make that would work well in the 25-06 rifles like mine that prefer shorter length bullets ? Thanks for any comments you have .

 

[RockyMtnMT]

Steve, I've followed with interest this thread about your bullets, I've owned 4 different 25-06 factory rifles through the years and am currently shooting a LR700 Remington . EVERY one of my rifles preferred the shorter bullets ( Example: Sierra 100gr Pro Hunter ) and shorter . I understand the 10" twist in my barrel is probably the problem, But am wondering why some have rifles that do well with the longer bullets with the 10" twist ??? Also, What bullet do you make that would work well in the 25-06 rifles like mine that prefer shorter length bullets ? Thanks for any comments you have .

We have one bullet for the 25cal that is designed for the 10" twist. The Hammer Hunter 92g. This one will shoot very well in your 10" twist.

As to why some guys can shoot some of the heavier bullets in the 10" twist and others can't may have something to do with the elevation. It could be the twist of the rifles can vary as well. Button rifled barrels can vary +/- on the actual twist up to 1/2". Couple that with bullets that are marketed for the 1/4 bore that are marginal for stability and it is easy to have them not shoot well. There other factors that come into play as well. Temp is a big one. A marginally stable bullet at 50* temp can become unstable with a significant drop in temp. Our 103g that is designed for 9" twist is a bit marginal at sea level with standard atmosphere (59*) and a 3000fps muzzle vel with an sg of 1.42. Take that same bullet and change the temp to 0* with everything else the same and the stability drops to 1.26sg. On the edge for shooting accurately. Run that same bullet with a muzzle vel of 3600fps and it is 1.51sg at standard atmosphere and 1.34sg at 0*. More marginal in this extreme condition than I would want to see, but should still work. This is another reason that one should try to shoot bullets that are better than 1.5sg for stability.

Steve

 

[9ptbuk]

We have one bullet for the 25cal that is designed for the 10" twist. The Hammer Hunter 92g. This one will shoot very well in your 10" twist.

As to why some guys can shoot some of the heavier bullets in the 10" twist and others can't may have something to do with the elevation. It could be the twist of the rifles can vary as well. Button rifled barrels can vary +/- on the actual twist up to 1/2". Couple that with bullets that are marketed for the 1/4 bore that are marginal for stability and it is easy to have them not shoot well. There other factors that come into play as well. Temp is a big one. A marginally stable bullet at 50* temp can become unstable with a significant drop in temp. Our 103g that is designed for 9" twist is a bit marginal at sea level with standard atmosphere (59*) and a 3000fps muzzle vel with an sg of 1.42. Take that same bullet and change the temp to 0* with everything else the same and the stability drops to 1.26sg. On the edge for shooting accurately. Run that same bullet with a muzzle vel of 3600fps and it is 1.51sg at standard atmosphere and 1.34sg at 0*. More marginal in this extreme condition than I would want to see, but should still work. This is another reason that one should try to shoot bullets that are better than 1.5sg for stability.

Steve

Thanks Steve for taking the time to explain this , I'll check the 92gr Hammer out .
B

 

[Schnyd112]

No joke on the marginal stability in 1:10 twist barrels. After having zero luck with 120 corelokt I had to measure the twist rate. It was actually a little slower than 1:10 and wasn't anywhere close to stabilizing them, I think 1.2 score at 6000 feet. Switched to 110 accubonds and haven't looked back. With it being such a popular deer cartridge, it seems ridiculous that 1:9 isn't the norm.

 

[RockyMtnMT]

No joke on the marginal stability in 1:10 twist barrels. After having zero luck with 120 corelokt I had to measure the twist rate. It was actually a little slower than 1:10 and wasn't anywhere close to stabilizing them, I think 1.2 score at 6000 feet. Switched to 110 accubonds and haven't looked back. With it being such a popular deer cartridge, it seems ridiculous that 1:9 isn't the norm.

You are absolutely right. 9" is actually slow for that small of cal. The thing is the cartridge was designed for shooting really flat to 300y with 100g bullets. Due to the huge number of rifles already out there the chance of seeing factory twist and factory ammo ever change is nil. Stick a 7-8" twist on a 25-06 and it becomes a different animal.

Steve