Hammer Bullets and twist recommendations

northhunter

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I did. It makes quite a difference. I also changed temp and humidity. All these variables are interesting cause depending on the year, I could be hunting in 25C or -30C and the humidity varies from 98% down to 70%. My bullets go from being good to being marginal depending on temp and humidity. It seems the baro is more of a constant between 100 and 103kPa. I think my next barrel will be a faster twist.
 

BFD Guns

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I did. It makes quite a difference. I also changed temp and humidity. All these variables are interesting cause depending on the year, I could be hunting in 25C or -30C and the humidity varies from 98% down to 70%. My bullets go from being good to being marginal depending on temp and humidity. It seems the baro is more of a constant between 100 and 103kPa. I think my next barrel will be a faster twist.
Brother, if you can keep all that calculated in your head at the moment of truth when you are pulling the trigger on the game than you are beyond my faculties.
 

Hand Skills

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Revolutions Per Minute has more to do with stresses on the bullet - at a certain threshold (north of 300,000rpm) cup and core bullets tend to come apart.

Hammers do not suffer this phenomenon

When it comes to stability, Revolutions Per Distance is the key.

My understanding is that as atmospheric pressure increases the center of pressure moves forward on the projectile, effectively increasing the leverage (due to the resistance of the medium - in this case atmosphere) on the bullet relative to the center of gravity.

-colder temperature increases air density
-lower elevation increases air density

This is observable with a barometer.

As air density increases, more Revolutions per Distance (a faster twist) is needed to achieve a given stability factor.
 

FEENIX

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Revolutions Per Minute has more to do with stresses on the bullet - at a certain threshold (north of 300,000rpm) cup and core bullets tend to come apart.

Hammers do not suffer this phenomenon
So does other manufacturers' monolithic/solid bullets.
 
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StanleyActual

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Anybody using the 134g or 139g Shock Hammers in a 6.5PRC? Swapping my daughters CM barrel out for a 6.5PRC. 22” 1:8T. Looking at the shock hammers based on her twist rate.

Any experiences or starting load data? This will be primarily for deer / elk inside 500-ish. 6.5 ain’t the best elk caliber but I figure these hammers hit above their weight class terminally so that should make up for it.

Appreciate the info!
 

Hand Skills

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Are these Hammers? They didn't perform like typical Hammers - even given the media?
I think the photo got uploaded in the wrong orientation. My interpretation is that the samples on the bottom were adequately stabilized, and the ones on top were marginally/under-stabilized.
 

Bret GRAVELINE Graveline

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Back in the 80's i horse traded into a very nice custom 25 06 built on a FN Supreme action, gun was middle of the road accurate, on a good day it would hold MOA, on a bad day it wold still hold 5 shots under 1.1/4 with 117 gr Sierra flat base bullets, most days were bad, while not my most accurate rifle the fabulous walnut made it hard not to love, figured I could make that 1 1/4 work, the same sierra bullet in a boat tail would double that group size, nor would it shoot any of the nosler bullets i had hoped to shoot, come to find out the twist rate was a 1 in 12, not knowing any better I used the FB Sierra for years on deer antelope and coyotes out to 500 & 600 yds, as new powders arrived I continued to experiment, I found reloader 25 greatly improved both accuracy and velocity, the rifle will now hold sub MOA with Nosler bullets the 110 gr AB and both the 115 gr BT and partition as well as the old 120 gr solid base, again not knowing any better or anything about rotational spin I continued to hunt using this load successfully out to 600 yds with great results, I'm still not totally up to speed on the whole rotational spin thing or the G1 vs G7 BC thing, but since all the cool kids are talking up the hammers I ordered 6 hammer bullet weights in 4 calibers, these were set aside for a winter project, in my selection was a box of the 110 gr hammer hunter to be tried in a 257 AI with a 1-9 twist, a hunting buddy has a Browning A-bolt in 25 06, he talked me into letting him try (have) the 110's, now his gun has a 1-10 twist, the hammers are intended for use with a 1-8.250 twist, a running of the figures showed that the 110 hammer was a better fit to the 1-10 twist than the Nosler bullets I was shooting in my 1-12 twist rifle, the 110 hammer bullets fired in the 1-10 25 06 shooting 3 3 shot groups produced a average of 6/10's, the average of the load he had been using 115 gr Barnes and Nosler averaged 3/4 MOA, he harvested two bucks this season using the hammers, both were under 75 yds, both ran off a short distance, not sure how the rifle and bullet will perform at longer ranges perhaps the slower twist will prove inadequate with more testing, at this point he is pleased,
For reference his old load was 55 grs of reloader 22 behind a 115 gr slug with a velocity of 3220 FPS, the new load was 52 grs of reloader 22 at 3190 FPS, while the powder is the same they are from different lots, the old load was loaded from a 8 pounder purchased over 10 years ago, while the new load was loaded from a much newer lot of 1 pounders, so give it a try and see what you get, half the fun is in finding what works and what doesnt, always something to be learned, good luck.
 
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