6mm Hammer bullets

[muleystalker]

The 110gr Hammers are a whole different animal than the 115 DTAC's and the Bergers.

 

[adam32]

The 110gr Hammers are a whole different animal than the 115 DTAC's and the Bergers.

Length, weight, BC and speed make up the stability factor...no different than every other bullet.

 

[Wedgy]

Length, weight, BC and speed make up the stability factor...no different than every other bullet.

It may fly straight and punch round holes in paper but staying straight and expanding properly when it hits game will be a different story. That how the Berger 195 initially got a bad rap, people were shooting it from 9 twist barrels and while it flew straight it would tumble or turn once it hit something and not expand as it was designed to do. Hopefully you can get a 7 to work, I had a hell of a time getting a 6 twist. Everyone says they can make one but the wait time stated is TWO YEARS, which in reality is probably three. I can't remember what I had for lunch let alone a wildcat 3 years down the road

 

[muleystalker]

Speed actually doesn't affect the stability factor as much as most people think.Like Wedgy stated the monos need to be spun fast to perform kill properly.

 

[HARPERC]

....I had a hell of a time getting a 6 twist......Everyone says they can make one but the wait time stated is TWO YEARS, which in reality is probably three.........

Like most companies barrel makers like to stay with volume. There is probably some doubt on their part about how serious the customer is as well.

Steve got me a 1-6" from Bartlein in about 6 months. A little extra cost to add tooling to make 32".

Could be they take a bullet maker more serious than they would a cold call.

I'd say if you're serious about a fast twist to shoot the Hammer's let them handle the build part of the project as well.

 

[adam32]

Speed actually doesn't affect it as much as most people think.Like Wedgy stated the monos need to be spun fast to perform kill properly.

We shall see...no monos before Hammers needed to be spun fast in order to kill properly and seeing as Hammers are softer than others, I'm not too worried about them.

 

[RockyMtnMT]

My 1/8 shoots the 115 Berger and Dtacs just fine in a .243 Ack. The 1/7 going a bit faster should been just fine with the 110gr Hammer. Length matters more than the material it's made of in my experience.

The 110g Hammer Hunter wants a min 6" twist. This is a very long for caliber bullet. The longer for caliber the harder they get to stabilize. I am guessing that you will shoot them sideways with a 7" twist.

 

[adam32]

The 110g Hammer Hunter wants a min 6" twist. This is a very long for caliber bullet. The longer for caliber the harder they get to stabilize. I am guessing that you will shoot them sideways with a 7" twist.

We'll see soon, Berger calculator says it's stable at my speed and altitude so hopefully it's correct. If not I'll just drop down to the 101gr.

 

[Deleted member 103481]

71 gr sledgehammer

 

[RockyMtnMT]

@adam32

The problem is this bullet is close to 6x caliber in length. 6x caliber in length seems to be the threshold where bullets have terrible dynamic stability issues.

I always do my calculations at sea level and don't consider elevation for hunting. What we see with the Miller stability formula is it was created at a time when there was no such thing as non lead bullets and there just wasn't long for caliber bullets. Thus the formula does not take into account material density. What we see is the longer for caliber bullets get the required twist needed goes up more rapidly. I would say that long for caliber bullets that are pure copper are fully stable at 2.0 sg at sea level.

It is interesting that our very long for caliber bullets shoot very well for some guys with the min twist and others shoot them sideways with the same twist. For a while I was going to remove several of the bullets from the site. Every time I was ready to delete a bullet I would get a report from a customer that is shooting it lights out. High air density plays heck on them. Also very high vel can cause issues. Makes them want to swap ends. We designed a 165g 6.5mm bullet for a 6" twist rifle that we have been working on for @HARPERC. It was shooting great until we broke 3300fps, then it started printing oblong holes at 200y. We have a customer that is running our 73g .224 cal bullet very well. Once he broke 3700 fps they started shooting sideways. The 83g .224 has these issues as well but worse. But then there is a bunch of guys that shoot it great.

I will be very interested in you results.

 

[adam32]

@RockyMtnMT

I had 1.5sg in my mind as your recommendation for stable for your bullets...so yeah I might be in trouble if 2.0 is stable on them. It'll be interesting to see how they shoot. I'm not too worried if I have to drop down to the 101gr, going a bit faster it'll kill like Thor's hammer!

 

[RockyMtnMT]

@RockyMtnMT

I had 1.5sg in my mind as your recommendation for stable for your bullets...so yeah I might be in trouble if 2.0 is stable on them. It'll be interesting to see how they shoot. I'm not too worried if I have to drop down to the 101gr, going a bit faster it'll kill like Thor's hammer!

For sure! We have not figured it out yet, but I think there is something to do with how a particular barrel engraves the bullet. The time needed to figure this out we don't have!

 

[adam32]

For sure! We have not figured it out yet, but I think there is something to do with how a particular barrel engraves the bullet. The time needed to figure this out we don't have!

I think you're right...I almost think a Lilja 3 groove might be the ticket for the uber fast twist higher speed stuff to get a deeper engraving.

 

[Deleted member 103481]

41-44 of reloder 16 in half grain increments might also do 3 at 43 or so since I'm trying to get him on a deer this year and then we can look for a rocket load in the off season.

most load data runs 42-46 but since I'm using lapua brass I'm thinking I would back it down a grain