Useing over size bullets

[CoyoteJoe]

Ackley also reported that during some tests he fired a 150 grain 8mm bullet in a modified 30-06 chamber which produced a pressure of only 40,700 psi compared to a standard 150 grain 30-06 at 57,300 psi. My guess as to why, is that the 8mm bullet is shorter than the 30 caliber of the same weight giving more freebore and reducing pressure at the critical instant while increasing velocity before the bullet had to swage down. This is pure speculation on my part because so many things stack up when discussing pressures in guns. Also while reporting on this he never mentions accuracy which is essential to the usefulness of a firearm. I am sure Ackley learned a lot from his experiments but he also blew up a huge number of guns doing it. I am no sage but my humble advice is to err on the side of safety.

Thanks, Diz

Ackley deliberately blew up guns, testing them to destruction to determine what they could take. BY so doing he contributed greatly to the pool of general firearms understanding.

[Diz]

CoyoteJoe,

You are absolutely correct about Ackley deliberately blowing up guns, I have done so myself but knowing that is the intention is one thing and doing it by accident is quite another. All I am saying is that given all the things that add and subtract from how pressures build in guns it is better to be careful.

Thanks, Diz

[CoyoteJoe]

CoyoteJoe,

You are absolutely correct about Ackley deliberately blowing up guns, I have done so myself but knowing that is the intention is one thing and doing it by accident is quite another. All I am saying is that given all the things that add and subtract from how pressures build in guns it is better to be careful.

Thanks, Diz

Well Diz, that may be "all you are saying" but given the context of the discussion you appear to be implying that Ackley blew up guns in testing the oversize bullet issue. I don't believe that to be true, nor do I believe he ever blew up a gun out of ignorance nor foolhardiness. If you are aware of any such incidents I'd like to hear about it.

[Diz]

Coyote Joe,

I never said Ackley blew any up unintentionally, what I said was doing it on purpose is one thing and accidentally is another. Take it however you wish.

Thanks, Diz

[mike ford]

Diz, Coyote Joe,
Unless my poor memory fails me, Ackley didn't start his testing because of a problem he had with a rifle; rather, he started because (post WW2) someone wrote to the "American Rifleman" ( an NRA publication), complaining about poor performance of his rifle that had been rechambered to 30-06. It turned out that instead of being a rechambered 7.7 Arisaka, it was a 6.5 mm. Naturally, this caused people to wonder just how strong these rifles were. P O Ackley endeavored to find out.
Mike

[Leatherman]

I didn't have time to to try some other bullet weights in my 10.5 X 47 double rifle before my match at Friendship Indiana last Monday. So I loaded up the 250 grain 44 magnum pistol bullet in front of 57 grains of 2f Swiss topped by a .30" fiber card and a 1/8" cork wad compressed about 1/8" before seating and crimping the bullet. Well I wasn't disappointed as I wound up winning the match hitting all 12 of the required targets on the first shot and missing two of the bonus targets which I lost points on. There were also 4 knock down metal targets that I hit but did not knock them over because of my lack of bullet weight and velocity. Knocking them down gets you 25 extra points each target. The way they had them set up only the .450 X 3" and larger calibers could knock them down. So I am very pleased with my double rifle and will be trying some heavier .429" bullets. Also I should mention I took a ketchup squeeze bottle filled with cold water along and squirted water down the bore after each shot, flushing the fouling out . It also cooled the barrels down a lot . Everyone else either used a rod and patch or didn't clean at all during the match. I had no leading problems and obviously no fouling problems.

[mike ford]

Leatherman,
That is great, I know you are happy, I'm happy for you.
Mike