.270 Win Ackley Improved - 270 WSM

[FEENIX]

Semi conventional
View attachment 471860
The bullets have been a large variety of 140gr to date.
130's and 150's not so much.

I'm really not a fan of heavies in .277.
I do however see the advantage in BC with added weight/length/solid-mono.
I've just been stuck in conventional 1:10 twist since the 70's
I suppose that if I ever got a quicker twist I'd be right in there pitching 165's

I'm looking at the WSM because I have a confusion of LR/AR-308 parts and a lathe ;-)
I should probably forgo any discussion about the .270 WSM and just neck a .308 to .277 and take out the body taper and sharpen the shoulder. In essence, 277-08 AI

Then stick with the .270 AI.

A fair portion of my 270 brass started life as 30-06 LC
Too bad the WSM uses a .505 face :-/
It's not like I have a glut of 404 Jeffery around.
So as above, .277-08 AI ?

Did you mean .540" +/-?

Good luck with your .27 chambering endeavor.

 

[kopcicle]

and tell all the 6.5 CM fans that the .277 is much more efficient lol.

I'd say it even if it wasn't true.
I'm getting a little sick of hearing "six five" in nearly every firearms discussion I'm part of.
As it is I get their goat with "I've been doing 6.5 since the '70's , where were you? I'm a huge fan of the 6.5x55 .

 

[kopcicle]

Did you mean .540" +/-?

need more coffee

It's the lathe I tell ya1
It's all the lathe's fault.
Once I straightened out threading and chambering life got interesting around here.

There is a reason and a need for professional gunsmiths. Although I have been accused of being a competent machinist, threading, chambering, reaming, action truing are a steep learning curve.
It's taken me years to have any confidence in my work.

And I'm still learning.

 

[xsn10s]

The .270 AI is a pre 64 70 medium profile Douglas 1:10 in Reinhart Fajen wood. Not that light but not a porker either. I didn't chamber this one. It came to me as is and is an old friend.

The plain Jane .270 is a BSA CF2 1:10 bone stock save for the trigger.
The trigger was a mess when I purchased the rifle and parts were hard to find. Oddly I never got a Timney to work. I understand that Timney made a trigger to fit the CS2 but I think I kept getting the wrong one. Out of frustration I built my own using what what was left of the BSA parts as a pattern.
Honestly I'd like to find another CF2 action to play with.

I have a JC Higgins FN Belgium Mauser. It has a chater chamber that I had a smith try to clean up. It's workable now but the chatter marks are still there. It's on the back burner as I have new projects to occupy my time with lol.

 

[choprzrul]

Can the 6.8 Western be reamed out to 270 WSM? You retain the faster twist barrel, and gain the extra case capacity of the 270 WSM. Lots more rifle choices for the 6.8.......

.

 

[CogburnR]

I have a 270 Sherman and several 270 WSM's. I use some of the exact same loads in both calibers. The main advantage of the 270WSM over the Sherman is factory ammo availablity, with an AI that isn't really even an advantage. My carry rifle is a 270WSM, but if I sit it is usually my 270-300WM(which is a good step up in performance).

 

[FEENIX]

I have a 270 Sherman and several 270 WSM's. I use some of the exact same loads in both calibers. The main advantage of the 270WSM over the Sherman is factory ammo availablity, with an AI that isn't really even an advantage. My carry rifle is a 270WSM, but if I sit it is usually my 270-300WM(which is a good step up in performance).

I can shoot .270 Win factory ammo in my .270 AI. Ackley designed his improved version to be able to shoot the parent cartridge.

 

[K.E.C.]

Semi conventional
View attachment 471860
The bullets have been a large variety of 140gr to date.
130's and 150's not so much.

I'm really not a fan of heavies in .277.
I do however see the advantage in BC with added weight/length/solid-mono.
I've just been stuck in conventional 1:10 twist since the 70's
I suppose that if I ever got a quicker twist I'd be right in there pitching 165's

I'm looking at the WSM because I have a confusion of LR/AR-308 parts and a lathe ;-)
I should probably forgo any discussion about the .270 WSM and just neck a .308 to .277 and take out the body taper and sharpen the shoulder. In essence, 277-08 AI

WOW, I am in the process of building a 277-08 AI 40* My thoughts are it should be just a hare slower than a 270 with a 22" barrel or just as fast. I will be cutting my barrel at 24 to 25" . Still waiting on a reamer from Manson's.

 

[CogburnR]

I can shoot .270 Win factory ammo in my .270 AI. Ackley designed his improved version to be able to shoot the parent cartridge.

Yup, the good thing with the AI. With the Sherman it isn't an option.

 

[FEENIX]

Yup, the good thing with the AI. With the Sherman it isn't an option.

... and so as many wildcats, which is different from the AI. I have 3 wildcats that I have to form the brass for it. I have hydraulic forming dies for two of my designs (.30 Lara and .338 Thor). My .30 Gibbs does not, so I must do a few processes to get to the desired brass.

(From L-R: .35 Whelen virgin brass, after re-sizing, fire-formed with 11g WSF (COW method), and after re-sizing).

Anyway, back to the topic, my apologies to the OP.

 

[kopcicle]

Anyway, back to the topic, my apologies to the OP

I'll gladly invite any comment on 35's in nearly any context.
I've been known to extol the virtues of .358 as part of thread drift in other's discussions.
How could I object in my own thread?

 

[nksmfamjp]

If I already have a .270 AI what are the advantages of a 270 WSM other than the more compact action?

I've spent a long time with .277" but none with WSM.

Well, no. The 270 AI should be cut for proper head height and twisted for your favorite bullet. It may not be, but should be since it was a build at some point. 270 WSM's are all cut low head height and twisted 10 twist. The idea was to shoot 130's at blazing speeds to be cool…..and to sell barrels I guess!

People buy WSM's, try 150's. They over seat them and they cannot twist them fast enough for decent accuracy.

if both are ground up builds, it comes down to brass. 270 Win has better brass selection. WSM only has ADG. Lapua is killing WSM, by not making brass, even though there are 300 WSM's that shoot lights out

 

[choprzrul]

I just ordered some Norma 270 WSM brass. Fallback plan is to neck up 6.5x270 WSM Bertram brass.

.

 

[akmtnhnt]

I think I'd to a 7mm-08 AI or SAW. But if you love the .277 then a .277-08 AI or .277-284 Win certainly would be entertaining . Or even a straight .277-08. Heck how about a .277 CM and tell all the 6.5 CM fans that the .277 is much more efficient lol.

277-08 is the 277 fury. You can just buy brass. Plus they did a 30 degree shoulder on it. I guess you could go 40 or 45 if you still want it to be a wildcat. Easy 1 shot fire form. Plus then you have the steel head option and well outrun a 270win.