270 Winchester Ackley Improved

I will have my 270 ai build back next week. Going start load work with rel 22 and 7828 and 130 and 140 pills

I've found R-22 and Imr 7828 worked the best with large rifle mag primers like CCI 250

130's don't have a good BC but they go pretty good with R-22 62 gr. 140 SPBT's 60 gr of R-22 and 150's with 58 gr The 7828 again with the mag primer uses about 1.5 grains more for each respective pill weight.

Of course start a couple of grains less on the powder and work up to these amounts.
 
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I will have my 270 ai build back next week. Going start load work with rel 22 and 7828 and 130 and 140 pills

The .270 Sherman will give you a 5% capacity increase over the A.I. with the same parent case. It is nearly identical in capacity with the WSM. I don't have a .270 yet, but my 6.5 gets 3150-3200 with a 140 berger and a 26" barrel.....Rich
 
I may have to go that route with my next one. I have another action sitting around. I was thinking a 6.5-06 ai but i am up to try anything. So the sherman would be similar to the gibbs correct?
 
I may have to go that route with my next one. I have another action sitting around. I was thinking a 6.5-06 ai but i am up to try anything. So the sherman would be similar to the gibbs correct?

It is nearly identical to the Gibbs in capacity but is a far better design. Longer neck, less body taper and sharper shoulder....Rich
 
The .270 Sherman will give you a 5% capacity increase over the A.I. with the same parent case. It is nearly identical in capacity with the WSM. I don't have a .270 yet, but my 6.5 gets 3150-3200 with a 140 berger and a 26" barrel.....Rich

Do you have a spec drawing of the sherman .277? With a tall drop tube I'm able to put in 65 grains of H1000 in my 270 winchester brass ai case. That is level to top. I have not done the grains of water. Using the standard new Win 270 case and H-1000 powder @60 grains is the most.

I shoot allot of rounds so I buy cheaper bullets for 98% of my shooting. The Sierra game king 150's (Spitzer Boat Tails) are a good choice

I also do the messy home moly coating.

Sierra Bullets - The Bulletsmiths
 
Do you have a spec drawing of the sherman .277? With a tall drop tube I'm able to put in 65 grains of H1000 in my 270 winchester brass ai case. That is level to top. I have not done the grains of water. Using the standard new Win 270 case and H-1000 powder @60 grains is the most.

I shoot allot of rounds so I buy cheaper bullets for 98% of my shooting. The Sierra game king 150's (Spitzer Boat Tails) are a good choice

I also do the messy home moly coating.

Sierra Bullets - The Bulletsmiths

My 6.5 Sherman holds 75 grains of H20 to the top, so the .270 would be slightly more. I do have a spec sheet for my 6.5 and my 300. The .270 would be the same except for the neck. Neck length on the .270 would be around .304".
 
where did you purchase the reamer? You have my interest up. I would like to go the 6.5 sherman route on my next build this spring. Should only have to neck size too, correct?
 
where did you purchase the reamer? You have my interest up. I would like to go the 6.5 sherman route on my next build this spring. Should only have to neck size too, correct?

I had Dave Kiff build it. I have a hydro form die that I use to form the cases for both my 6.5 and 300 but I have also fire formed them. If I use .270 cases for the 6.5, I simply neck to 6.5 and leave a false shoulder to headspace. I use 11 grains of red dot, fill the rest with corn meal, and a little cotton to hold it together.......Rich
 
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