270AI !!

[quickdtoo]

Here's the target I shot today at 75yds and the fire formed cases with a factory case on the left for comparison, the vertical string is 3 150gr Nosler partition handloads fired back to back, the high right shot was a factory 130gr load that Jack shoots in his 270W Browning. 

Tim

[Fred M]

Mac.

A 348Win at 2.255" will never clean up a 270 chamber at 2.540" not in a Handi. You woud need to cut off the barrel .285" at the chamber end.

[Mac11700]

Mac.

A 348Win at 2.255" will never clean up a 270 chamber at 2.540" not in a Handi. You woud need to cut off the barrel .285" at the chamber end.

It wouldn't if you kept it as a stock factory 348 Win..but..since the head area will clean up nicely .553 as compared to .470 and you can improve it out to a shoulder diameter of .490-.495..and going with anything larger than a 30 cal you will be able to remove the entire 270 chamber..this is especially true boring it out for a 375 cal lede and throat..atleast this is what I have been told by a few good smiths..

Mac

[quickdtoo]

At this time I don't think a rebore is in consideration, but I don't think the 348 Imp would clean up the 270 shoulder at since the 270 is longer at the shoulder 1.984" compared to 1.752" for the 348 Impr , and the 270AI shoulder is even further forward, not according to Steve's and AmmoGuide's drawings anyway. AmmoGuide says it can't be done on a 270Win, they don't list a 270 Ackley in their data base, I didn't see any of the 348Win wildcats listed either.

Tim

http://stevespages.com/jpg/cd270winchester.jpg

http://stevespages.com/jpg/cd348wcfimproved.jpg

[44 Man]

Quick, if you stop the vertical stringing, you'll have a real shooter there!  44 Man  (I still think you should call it a .279 Quick Improved)

[Mac11700]

At this time I don't think a rebore is in consideration, but I don't think the 348 Imp would clean up the 270 shoulder at since the 270 is longer at the shoulder 1.984" compared to 1.752" for the 348 Impr , and the 270AI shoulder is even further forward, not according to Steve's and AmmoGuide's drawings anyway. AmmoGuide says it can't be done on a 270Win, they don't list a 270 Ackley in their data base, I didn't see any of the 348Win wildcats listed either.

Tim

http://stevespages.com/jpg/cd270winchester.jpg

http://stevespages.com/jpg/cd348wcfimproved.jpg

Well..it can work if you rebore..but since your not..the point is moot then..


Good Luck with it

Mac

[quickdtoo]

A lot of that vertical stringing was shooter error, the rest I was using wasn't very good, I had a lot of teter-totter affect with the muzzle floating up and down, not so much side to side, I wasn't very steady at all, I didn't bring my shooting table or rests since I had all the hunting gear for 3 of us loaded in the little Toyota plus the game cart, we were tired and all wanted to get home, so I just made a quick stop and shot the 4 rounds and headed for home. I have 4 fire formed cases to do a little testing after the next hunt later this week, I think a couple of em will be a 130gr Speer .284" bullet loaded in a neck turned case with a 270W start load, I keep thinking of the guys that shoot .311"-.312" milsurp in their .308" bored 7.62x39 rifles and vice versa, so .277" or .284" bullets should work in the .280" bore. 

I just got a reply from Rick Tunell on the .280" sizing die, he can make it for me if I decide to go that route. 

thanks,

Tim

[bluebayou]

I know that you want to use that big old brain of yours, but.......have you tried it near max loads with regular .277 bullets yet?  Maybe I am not following, but is the cart before the horse?   

I know that the 44 Mag barrel that I had with .432 bore wouldn't group well with .429 Hornadys.  But, the .308 Noslers that I shot in my SKS worked well enough at 3 MOA (hey, it is an SKS).

[quickdtoo]

Yes, that's the first thing I'll try when I have a full range day to spend, this is just for a few test shots, that option was the first one that I expected to do, but won't happen for a while, for one thing I need to make a bunch of fire formed brass to work with first. 

Tim

[dieselten]

Tim,

Another solution is Hawk Custom Bullets.  http://www.hawkbullets.com/custom.htm

They will custom make their vast selection of bullets in larger diameters or with thinner jackets(bump up easier).  Their prices are very reasonable.  I am thinking of having them make a jacketd .379 diameter 255 bullet fro my Handi 38-55 with .382 groove.

Nick

[quickdtoo]

Thanks, I'll keep it in mind. 

Tim

[AtlLaw]

A lot of that vertical stringing was shooter error,

Shim induced?      Sorry Timmy, I just had to... 

This is a great thread!  Ya see, I got this 270 Bbl laying around and you was gettin me all fired up with this 270 AI stuff!  Then you start your worrysome talking about bore problems!  But it doesn't look like you're going to have any accuracy problems that are bore induced to me!     An inch and a half, all vertical, with fire forming loads!?  What do you want!?   

What you need to do is get it shooting as good as you can with .277 bullets, then buy you one a them bullet squeezers and run a few down to .279 - .280 and see what you get!

Me, I'd be satisfied with the inch or 1.25 inch I'll bet you're gonna get from that barrel...    But then you ain't me... 

[quickdtoo]

Yup, I hear ya Richard, but I gotta try some .284" bullets just for fun, I figured with the added chamber volume of the Improved chamber, use 270 start data to fire form a few cases shouldn't be a problem unless the pressure is just too much, the first shot should tell me if it's going to be a problem, hard to press release button, flat primer or sticky extraction, the usual suspects of too much pressure in a Handi, and of course how accurate they are if I shoot more than one. 

BTW, no shim makin here, I haven't had a beer or any kind of alcohol in a loooong time, I still have 3 bottles of micro brew in the fridge that I bought in 1998, I drank one, used the other two for a loaf of bread and some fish fryin batter!! 

Thanks,

Tim

[AtlLaw]

BTW, no shim makin here, I haven't had a beer or any kind of alcohol in a loooong time,

AWK!!    Just the thought of that is to much of a shock for my system!      where's my nitro pills... 

[petemi]

Cheers 'n Shims.

Pete