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Slapp
01-10-2014, 03:00 PM
Let me start by saying I am new to the whole reloading deal and I think I overloaded myself with information.
My question is this; I ordered some Hornady 168gr Amax bullets to reload some once fired (from my rifle) brass, plan on using cci large primers, Varget powder. The main question is the Amax bullets say on the box "recomended for 1 in 12 twist or faster and my rifle is a 1 in 10 twist? Affects...does it matter... what do you think? I plan on F/TR class out to 600-800 yards or better once I learn more and do some matches.

sledder12
01-10-2014, 04:18 PM
Your twist is faster.

pitsnipe
01-10-2014, 04:28 PM
Also can look at it as "tighter" One full revolution of the bullet per 10 inches. Versus, one full revolution of the bullet per 12 inches. The smaller the number, the more stable/aerodynamic a larger/heavier bullet will be. This in perspective with its caliber of course. But a 1 in 10 .30 caliber barrel can better stabilize a 200 grain bullet than a 1 in 12 can. Out to 800 you should consider a 175 grain vs the 168. It will buck any wind better due to its higher BC.
Good luck in your match's.


Snipe

eddiesindian
01-10-2014, 09:43 PM
roger that on all the above.
the heavier the bullet, the closer/tighter the twist...the lighter the bullet the longer the twist.
dont know your twist or lenght of barrel but a buddy of mine worked up an accurate load using 168 a-max and 42.6grs of tac for his model 10 24"...1/10 proved worthy

earl39
01-10-2014, 10:11 PM
To be more exact it really has little to do with weight and more to do with the length of the bullet. The longer the bullet the faster twist needed to stabilize it. Notice that a 240 grain bullet from a 44mag will use a 1-16 twist but a 220 grain (note it is 20gr lighter) 30 caliber bullet needs a 1-10 twist.
Your 1-10 will do fine with the A-Max. As noted by pitsnipe above the 175MK or the 178 A-Max will out preform the 168 at the longer ranges.

eddiesindian
01-11-2014, 01:57 AM
168,s work wonders for me...even at 1K
Its all about speed and altitude.
in regards to length of bullet.......I believe weight/longer lenght go hand in hand....they gotta put the lead/copper some where. I know there may be exceptions ex: 68gr Hornady in .224 is longer than a 69gr. SMK.

MacDR
01-12-2014, 09:56 AM
The length to weight ratio is dependent on bullet construction and profile. At two extremes you have flatnose bullets of solid lead construction such as the Beartooth LMN @ .980 and at the other all copper spire points ones such as the Barnes TSX @ 1.318. Both 170 grain .30 caliber bullets. While in a 1-12 barrel the hard cast bullet is solidily stable @2600 fps, the copper one is marginal even when pushed faster @ 2800 fps. (Comparisons using Berger Bullets Stabilty Calculator.) In jacketed bullets the extremes are flat based, round nose bullets versus VLD's. I also endorse the SMK in 175 pushed at the fastest speed that gives you best accuracy and remains below published max loads. Wayne Van Zwoll has a couple of books on long range shooting you may wish to read.