Why Hammer Bullets Are Always Faster

[choprzrul]

A change in resistance to getting pushed down the barrel will surely effect a bullet's velocity also, correct? Alloy composition will effect hardness, a 0.0001" difference in diameter will effect resistance going down a bore, bullet shape such as a bore rider design effects bore resistance, etc, etc, etc....

To me, it seems like an over simplification to say pressure is the only thing that can effect velocities. 60,000 psi of pressure will surely produce different velocity if 2 bullets that weigh the same have different hardness, diameters, and bullet shapes?

.

 

[Hard rock]

A change in resistance to getting pushed down the barrel will surely effect a bullet's velocity also, correct? Alloy composition will effect hardness, a 0.0001" difference in diameter will effect resistance going down a bore, bullet shape such as a bore rider design effects bore resistance, etc, etc, etc....

To me, it seems like an over simplification to say pressure is the only thing that can effect velocities. 60,000 psi of pressure will surely produce different velocity if 2 bullets that weigh the same have different hardness, diameters, and bullet shapes?

.

The drive bands reduce friction and drag compared to other bullets ,they also have a double radius . My experience is more vel with less pressure , everything else being equal . It really isn't that complicated . You can load from book data with similar weight bullets , example Barnes data , start low work up too max and leave it at that , or if you are a experienced and confident reloader , 99 percent of the time you can move up in powder charge and achieve more vel without pressuring out compared too a like bullet in weight or composition, or both. That's the way I do it with some really impressive velocities, with Hammer bullets.

 

[Lou270]

Your post is still meaningless. Most of us don't have pressure testing equipment.

Which is why manufacturers publish load data. If the velocity you are seeing exceeds what is published for a similar bullet it is probably higher pressure.

I am not saying Hammers do not get higher velocity. I don't know and neither do the folks at hammer until they have pressure tested data. Maybe they do and have not shared it. I would like to see it and would gladly use their data.

Until then I have been using barnes tsx data for hammers as guide. This is what hodgdon, a powder company with pressure testing equipment, recommends.

Lou

 

[dogz]

One of the many challenges with manufacture data is that a lot of it isn't actually tested but a swag via quick load.

Hodgdon is actually pressure tested.

 

[Varmint Hunter]

When I started coating bullets years ago, the first thing I noticed was a reduction in velocity due to a reduction in bore friction. Uncoated bullets always shot faster with the same load.
The Hammer results are interesting because my past experience would leave me to believe that if the Hammers were producing less friction, then they would also show a reduction in velocity. The fact that the OP found the velocity to be increased lead me to conclude that the pressure must be higher, not lower.

It would be interesting if someone who had pressure testing equipment would actually check the pressure of the two different bullets with the same load. This is the only way to, conclusively, know the answer.

 

[Fiftydriver]

Absolutely 100 percent meaningless without pressure testing results. Not saying hammers do not get more velocity but this proves nothing. different bullets often get higher or lower velocity with same charge weights. Does not mean pressure is the same nor does "no pressure signs" means ok.

Lou

Loaded to same pressures, Hammer bullets will always be faster then any other conventionally designed bullet. Simple matter of reduced bore contact, less friction. Often times the same load used with both bullet types will result in less velocity with the Hammer simply because they slip down the bore with so much less effort and pressure is much less, however when pressures are brought up with the Hammers, their velocity potential will be significantly higher at same pressures.

taking it even to the next level, you can often drop down to a faster burn rate powder with the Hammers which will again offer a boost in velocity potential. Also reduced bore temps as well because of the faster burn rate powder. May be hard to measure but barrel life will be improved as well.

 

[dogz]

I've said this before, but remember the days 30 years or so ago when we wanted in the worst ways to get a decent chronograph for money we could afford.

Well, IMO that's where we're at now a days in terms of pressure testing equipment. I'm betting/hoping that in the next 5 or so that someone will come out with a reliable pressure testing system that is affordable (say sub 1K). Then it'll be interesting...all those I'm getting this triple X speed with no pressure signs may well have another story to it. Maybe..........

Kind of like all those pre LRF 500 yard shots that became 300 yarders after we had a good LRF

 

[Hard rock]

Loaded to same pressures, Hammer bullets will always be faster then any other conventionally designed bullet. Simple matter of reduced bore contact, less friction. Often times the same load used with both bullet types will result in less velocity with the Hammer simply because they slip down the bore with so much less effort and pressure is much less, however when pressures are brought up with the Hammers, their velocity potential will be significantly higher at same pressures.

taking it even to the next level, you can often drop down to a faster burn rate powder with the Hammers which will again offer a boost in velocity potential. Also reduced bore temps as well because of the faster burn rate powder. May be hard to measure but barrel life will be improved as well.

Yes sir , you are 100 percent correct.

 

[dogz]

bottom line, keep them all at the same pressure levels and then see what's what...one can play the speed games all day long. We all know a truck load of ways to tip the scales one way or another right........

 

[RockyMtnUT]

I love it when people use the term "always" or the "best".
It almost always results in confrontational arguments.

Thanks for the information presented.

 

[QuietTexan]

One of the many challenges with manufacture data is that a lot of it isn't actually tested but a swag via quick load.

Yup.

Berger openly admits that when they give you load data that it comes from QL.

That means it's no different than me running QL on Hammers.

That means my Hammer loads are no worse than any Berger load data I've ever received from Berger directly.

I'm not worried, if the gun doesn't blow up it's fine Bergers and Hammers, either or.

 

[Leaf Litter]

Yep....pressure equals speed and speed equals pressure.

No magic to it, just the way it is

Just watched the video, primers were shown with the 69's post firing and they looked like they'd had plenty. Primers post shooting not shown with the 70's.

It's more complex than "pressure = speed" like you claim. Pressure equals force, the resistance of the bullet to travel is a force vectored in the opposite direction. Shooters tend to lump this all in with bearing surface, but a number of geometricand metallurgical factors play in also.

I think the thesis here is that hammers have a smaller total surface area touching the barrel and more area for displaced metal to fill without binding which helps create more velocity from the same powder charge and/or peak pressure.

 

[Hard rock]

I love it when people use the term "always" or the "best".
It almost always results in confrontational arguments.

Thanks for the information presented.

There are only discussions , until remarks like you just made , that causes things to become confrontational. May I ask why you are always negative towards Hammer Bullets ? No one is making you choose any thing that is your freedom of choice too like what you like and discuss it accordingly, The OP posted a question and we are trying to answer it , some answers are better described than others .

 

[Hard rock]

There are only discussions , until remarks like you just made , that causes things to become confrontational. May I ask why you are always negative towards Hammer Bullets ? No one is making you choose any thing that is your freedom of choice too like what you like and discuss it accordingly, The OP posted a question and we are trying to answer it , some answers are better described than others .

If I took your post out of context , no offense intended . My apologies.