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+p Ammo In '27a1?


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#1 TN.Frank

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Posted 20 March 2004 - 03:46 PM

I know that the Thompson was mainly made for 45ACP military ball ammo BUT would it hurt the gun to shoot +P ammo in it? I'm thinking for home defence that a good 185gr-200gr HP in +P would be a better "stopper" and offer less structural penetration then 230gr ball ammo. For general plinkin' and having fun ball would be find but I'd like a good HP for use as a defence round.
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#2 PK.

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Posted 20 March 2004 - 09:30 PM

I have to disagree with you on this one Phil, at least partially.

The 27a1 is straight blowback with a bolt having marginal mass for the job. Bolt velocity with standard ammo is pushing it as is. That said, will +p “blow up” the gun? Not likely. If the use is limited as Frank has indicated he should be ok, but a steady diet of +p would not be advisable for the 27a1 IMO.

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#3 Randy Lish

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Posted 20 March 2004 - 09:52 PM

I'll share something that personally happened to me. One day while at the range shooting my Savage 1928a1, I noticed that I was almost out of practice ammo when I spied a left over box of Remington .45 + P 185 gr JHP in my shooting bag and thought " let see what this will do ". So I loaded up a 20 rd mag and let'er rip. It sounded like one very long shot
( kinda like a mac 10 ) and the gun stopped. I thought it must have jammed, but I found the magazine was completely empty and I was now being showered by falling brass. Later in the week while I was talking with Stan Andrewski on the telephone, I shared my range experience with him. I asked if that Remington .45 + P ammo would accelerate the RMP's my Thompson exhibited and his response was " Sure it could and it'll crack the back of your receiver if you keep using that ammo " Based on that sound advise, I only use factory practice type
( Federal red box, etc., etc. ) in all of my Thompsons.
Best Regards
Randy
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#4 TN.Frank

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Posted 20 March 2004 - 10:55 PM

So my best bet would be something on the order of a 200-230gr HP loaded to standard pressure to insure a long life for my '27. The reason that I ask this question here is because it is a blow back action. On an action that "locks" pressure isn't as much of an issue because the action won't unlock until pressure has dropped to a safe level but with a blow back spring pressure is all that's holding the action closed and if you over pressure you could eject the case while the pressure is still higher then it should be an damage the gun. I'll check into some standard pressure loads like the Federal "personal defence" load. That may work well. Thanks for the help guys. Talk to ya' later. cool.gif
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#5 John Jr

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Posted 20 March 2004 - 11:02 PM

Use a shotgun for home defense.

Overpowered ammo in a self defese situation would be ok. More than likely you will never have to defend youself, but if you did and you cracked a Kahr or WH Semi, you wouldn't be out all that much money anyway.

I would be willing to destroy my own 28 Savage if I had to crack the receiver to save our lives. But the military used ball ammo, and thats what I use. It worked for them.

Shooting a perp with a one second burst from a Thompson delivers 2300 grains of lead and a whopping 3500-3800 foot pounds of energy. I believe these numbers beat a shot gun blast, but most folks dont sleep with their thompson (I have once or twice). Shotguns are easy to get for under 200 bucks. The damn transfer tax on a Thompson costs that, so thats why I say "Use a shotgun for home defense. "

Jr

Here is some interesting reading about the 45 Acp I found.

http://www.sightm191.../Care/45acp.htm


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