25-06 ackley
I'm looking very seriously into having a 25-06 browning A Bolt reamed to ackley improved. I reload and the dies are easily obtained so thats not a problem. My question is are there any downsides to having this done I have had a sako reamed to 7mm stw and am very happy with it. I just want to know if maybe there is something I'm not thinking of about the procedure or the Browning or the caliber that could go wrong.
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Your 7 STW needed only to have the chamber lengthened but "improved" cartridges are a little different. They are set up so that standard ammunition can be fired in them routinely. Usually the barrel is set back and then the improved chamber reamer run in to the point where the standard cartridge makes a slight "crush fit" at the shoulder/neck juncture. As you can see, this entails a good bit more work than just running in the reamer. 0 -
I've learned something already. I was actually thinking it would just be a simple thing to ream it to fit ,but the shoulder angle is different so it can't be that easy. I guess it will cost more than my 7mm stw did. Thanks 0 -
bandcollector,
While this is an adequate description you shouldn't jump to the conclusion that this will mean more money. The gunsmith has to pull the barrel anyway to do a proper job of reaming the chamber so the tiny bit of set back can be included in the cost. The set back is usually the equivalent of one thread in order to get the barrel back to top dead center. For a 16 TPI tenon (Remington, Winchester, Weatherby, etc.) that amounts to 0.0625" and if it's a Mauser with a 12 TPI tenon, it's about 0.083" which is not much in the world of machining. I wouldn't get too excited.
The A-Bolt is a fine rifle just not as prevalent as the Remington or Winchester rifles.
The .25-06 cartridge is superb for long range hunting and punching holes in paper targets at long distances. It is a little out of proportion with the lighter bullets especially when confined to the shorter barrels so popular today. But when matched up with the heavier hunting bullets or the Berger Match bullets, it really starts to shine.
Ackley Improved cartridges do not show pressure signs the same way that standard cartridges will so pay close attention to working up your loads. Find as much reloading information as you can and follow it until you gain familiarity with your chamber and the cartridge. There are several .25 caliber fans on the Gunbroker Forums so we should be able to assist when needed.
Best.0 -
bandcollector,
As nn noted the cost will pretty much be the same as a re-chamber. It's not a big deal to do this job and the rifle, I believe, is a good one to handle it.
That being said I will say something in favor of the improved cartridge. I've recently had enough time on my hands lately to shoot some local competitions. Of the many competitors I know who shoot some kind of improved say that the biggest thing they get is extension of case life.
The straighter walls grip the chamber sides better. Therefore it reduces (not eliminates) brass working while firing. You can still loosen primer pockets by loading too hot, though. So do take care to look for the latest in .25-06 improved information.
As for the shoulder angle, it varies with caliber as to which is the best. To explain this, the bottle neck cartridge creates an impediment to flow that increases pressure. If you were to picture the two extremes one would be a straight wall cartridge that you never get enough pressure out of to launch a bullet @ 3000 fps and the other would have a right angle shoulder. The right angle shoulder would hold (impede) pressure so much that it would become a bomb in itself because it wouldn't flow out of the case. So you want to build higher pressure and then have it flow from the case.
Ackley pretty much standardized 40 deg. as his thing. RCBS came along and said 28 deg. was the best. Ackley was pretty much looking for more room in the case for more powder. He felt it was as high as he could go without impeding flow. RCBS was looking to increase pressure flow as they felt 40 deg. held up the pressure possibly. Anyhow along comes Winchester and the great ideas of the WSM and WSSM cases. They run from 32-35 deg. Tubb runs his 6mmXC at 30 deg. So somewhere in between is a number that will maximize both pressure and flow. The two most common dies you'll find are the Ackley and RCBS, of which the Ackley is way more popular. Both will work fine as an improvement over the standard 25-06.
Personally, I would do it. It's a fun cartridge to work with, especially, if you want to get out and do some long range work. You might look into barrel with a tighter twist than a 1-10" someday, so that you can stabilize the longer bullets. Wildcat makes up to a 142 gr. .257 bullet and GS Custom from South Africa Makes an Uber-long target bullet. This is where the .25-06 Improved will really shine. Like one-mile shine. However, if you stay with a 1-10" (your barrel), you will be able to work with the Berger 115 VLDs that do pretty well themselves.0
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