Hammer Hunter question 270Win

[emp1953]

I am shooting a SIG 970shr .270Win with a 1:10 twist. I have a pet load of 51.4gr IMR4350, 150gr Nosler ABLR ( one inch at 225yds) CCI200 primers, New Federal cases. (150 gr Nosler partitions give 1.6 inch at 225 yds) Both are around 2900fps.
Given pandemic shortages, and no availability of Nosler bullets I picked up 2 boxes of Hammer Hunters 156gr and 2 boxes 140gr. I backed off the powder a bit for the 156's fiddled with powder and seating depth and couldn't get any good groups. I moved to the 140's and immediately hit a node which is better than my one inch at 225yds. Could the fact that the 156's are longer than the Nosler 150gr ABLRS and make the 1:10 twist barrel unable to stabilize them? Just wondering. I'm happy with the 140's and will be hunting with them.

 

[jeremy.b]

The 156s and for that matter the 140s all call for faster than 1-10 twist.

Running the numbers for the 150 ablrs also show marginal stability unless higher than 5k ish elevation.

Getting groups is one thing, terminal performance on game is another. That is why hammer recommends the twists they do to ensure consistent terminal performance when smacking into meat and bone.

As a data point; I have a 270 that never liked any bullet that showed marginally stable in it's 1-10 twist. I run the 133 shock hammers for now. That is the biggest reason I'm swapping to a faster twist (1-7) on that gun so I can comfortably run longer pills.

 

[Raudy707]

Hammers are really long! They show minimum rate of twist on every bullet on their website and they mean it! Send those bullets back and get some 117 or 124's. A 133 shock hammer will also work for you 1:10. Even though you got the 140's to shoot you should talk with Steve because most likely they are marginally stable and once they lose velocity after a few hundred yards they will keyhole or not expand correctly when they hit an animal. The minimum rate of twist is very important to terminal performance for the Hammer bullets. But those little 117's pushed really fast will astonish you how they kill big animals.

 

[Raudy707]

@helsyeah exactly 100%. We both said the same thing at the same time. Ha

 

[emp1953]

Thanks guys.

 

[dogz]

elevation where you're at?

My 10 twist .270's shoot the 165 Matrix just fine here in SWMT (range ele about 4500')

My NULA perks well with the 117's and H4831 at just sub 3300 fps

 

[JAYgs8163]

The 156 hammer hunters require a 8 twist or faster to stabilize. The 140's require a 9 twist to stabilize. Per Steve at Hammer you really need to follow their guidance on twist rates required. I learned the hard way also.

 

[SSgt G Cody]

I've loved AccuBond and Cap-&-Core bullets for many years, but now have fallen in love with the long, sleek, tough Hammer Hunters! They can be 1/3 lighter in weight, and still outperform most designs much heavier because of their tough, solid construction! The lighter weight means they are very fast and accurate too! Their high energy literally DROPS big game!

 

[FEENIX]

I am shooting a SIG 970shr .270Win with a 1:10 twist. I have a pet load of 51.4gr IMR4350, 150gr Nosler ABLR ( one inch at 225yds) CCI200 primers, New Federal cases. (150 gr Nosler partitions give 1.6 inch at 225 yds) Both are around 2900fps.
Given pandemic shortages, and no availability of Nosler bullets I picked up 2 boxes of Hammer Hunters 156gr and 2 boxes 140gr. I backed off the powder a bit for the 156's fiddled with powder and seating depth and couldn't get any good groups. I moved to the 140's and immediately hit a node which is better than my one inch at 225yds. Could the fact that the 156's are longer than the Nosler 150gr ABLRS and make the 1:10 twist barrel unable to stabilize them? Just wondering. I'm happy with the 140's and will be hunting with them.

Yes! Monolithic bullets are longer because that is the only way they can increase the weight, and the longer the bullet, the faster the barre twist requirement to stabilize them.

The bottom line for me, I follow the minimum barrel twist recommendation of the bullet manufacturer regardless of altitude, but that's just me.