What’s the limiting factor of 45acp?

Csinn

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Me and my brother in law were in a conversation the other night about this caliber. He recently purchased a 10mm and I am purchasing a ruger Blackhawk 45 colt. We both mentioned that we had looked at 45 acp but after really looking at it it’s really a pretty narrow use cartridge as far as bullet specs atleast factory ammo. Good for self defense but not for hunting really or wilderness protection against bears, large predators. We wondered why can’t the 45 acp equal a 10mm? It has heavier bullets but why can’t it be souped up to similar power? Is it the case? Firearms? Just no interest? What am I missing?
 
... we had looked at 45 acp but after really looking at it it’s really a pretty narrow use cartridge as far as bullet specs atleast factory ammo. Good for self defense but not for hunting really or wilderness protection against bears, large predators.
It wasn't designed as a wilderness protection round. It is military/personal defense round.

Here is a Mike Venturino article in American Handgunner describing the best revolver cartridge.

 

What’s the limiting factor of 45acp?​

The shooter.

When it comes calibers and firearms it is always the shooter. The reason I say this is because a firearm is nothing more than a tool. A certain tool has one main function but we tend to change that by being curious, and testing its limits. Each firearm in the industry has its limitations as well as calibers, no single firearm or caliber is a do all. Decide its purpose and use it for that purpose.
 
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45 ACP FMJ will shoot through two full-size gelatin blocks back-to-back and keep going.

45 ACP with expando bullets penetrates to the same depth as all other major calibers shooting expando bullets.

So what's the issue?

Remember too, there's 45 Super. Works on most 45 ACP guns without any modification. Except you might want to see how it functions with heavier recoil spring to minimize beating the gun up. 45 Super uses a case that is thicker in the web, because the first limiting factor on "hot-rodding" 45 ACP is the brass cartridge-case, and not the guns that shoot it.


Only issue I see is 45 ACP guns tend to be the heaviest, and carry a few less rounds. Maybe somebody will bring up 10mm and "bears" or some such. OK, bears then. If you're gonna shoot a bear with a handgun, be sure to shoot a bullet that doesn't have a real conical-shaped nose. Because any bullet at handgun speed does risk bouncing off bone on its way to wherever bullets that bounce off bone go. Remember, you are 99.9% more likely to be attacked by a crack-head in a wife-beater than a bear. Probably even in Alaska. So there's that.

You shouldn't have to spend a fortune on 45 Super ammo, because how many bears will you really have to shoot?

Now, if you want a lightweight, high(ish) capacity carry piece, get you one of the plastic-fantastic guns that are popular these days. Then and head on out to the 7-11 for a corn dog and some smokes. Aint gotta dress up like John Wayne to go everywhere. Not that I would hold it against you if you did.
 
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https://www.vihtavuori.com/reloading-data/handgun-reloading/

https://www.vihtavuori.com/reloading-data/handgun-reloading/

Load data of 10mm tested from 5 1/2" barrel vs .45ACP 5" barrel. Compare bullets of similar weight and you'll see there's not much difference. So the limitations have to be in reference to factory ammo, I'd guess? Except most of the shelf 10mm ammo is basically.40+P if you're lucky. But the good stuff from Buffalo Bore or Cor-Bon? They make it for .45ACP too. So, does .051" larger diameter at roughly the same velocity hinder a pistol bullet's performance that drastically at pistol ranges?

To me, the biggest limiting factors of .45ACP are in the minds of the naysayers who automatically disregard any cartridge measured in decimals. Or the 2 fewer rounds in guns of the same size. Which then also applies to the ,45LC...

Souping up a 45ACP isn't really necessary to get close to 10mm capabilities. The folks that run 45 Super or especially 460 Rowland are going after bigger fish.
 
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I think sometimes we get to caught up in trying to soup up calibers. A lot of times it might be better to just buy the cartridge with the appropriate power level.

I'm not pointing fingers; I've done this many times myself. The 10 mm is a great round as is and doesn't need to be jack through the roof to work well. The same could be said for to the 45 ACP.

For those wanting to use the 45ACP for wilderness protection, here is a great option that would work in most 45 ACP guns:

Lost River Ammo

A similar load can be constructed for use in all .45 ACPs if you reload. A 230/250 grain bullet moving over 800 FPS is going to penetrate and carry a decent amount of energy.

Sometimes it's good to remember what our forefathers were are able to do with their contemporary technology when there really was a ton of toothy critters and angry enemies.

I love new calibers and new guns, but a lot of times that leads us to overlook well vetted, existing options.

For me, the 45 ACP is proven and can be used in many different roles. I will always have a couple in the safe.
 
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If you're looking at SD from 2 legged predators 45 ACP is good enough, I don't see any advantage to 10mm. The only downside is reduced magazine capacity. If you're looking for large predator protection a 200-220 gr 10mm bullet is going to give much better penetration than anything you can do with a 45 ACP. And if you have to stop a large predator deep penetration and shot placement trump everything else.

Some of the 255 gr hardcast 45 bullets will probably do pretty good. Some of these are running about 900 fps, but still won't match 10mm for penetration.

In fact if you want penetration the 147 gr 9mm loads are the king. I saw a test a while back where they used 60" of gel and still didn't catch the bullets. Thats 5' and the bullet didn't stop.
 
I've known or read of.people who have successfully killed deer size game or defended against a black bear attack with 230gr FMJ. Parr of that is most likely shot placement.

I personally have no experience with.45 fmj other than 2 legged threats.

YMMV
 
It wasn't designed as a wilderness protection round. It is military/personal defense round.
And as a horse-killer for mounted troops and/or Cavalry. Mounted use is the "why" for having the various safeties, also all the lanyard loops.

Sometimes short, fat and slow just has to do.
Hey, I resemble that! :)
 
I think sometimes we get to caught up in trying to soup up calibers. A lot of times it might be better to just buy the cartridge with the appropriate power level.
I think is key. If one has to modify any weapon to shoot totally something different than what it was developed for just get one with the appropriate power you want.
I always hear or read how can I make a .380 shoot like a 9mm or a .38 like a .357, why not just buy what one really wants.
 
And as a horse-killer for mounted troops and/or Cavalry.
This. Hitting his horse was nearly as good as hitting him.
Have a lot of respect for punkin-roller rounds. My standard .45 Colt load, from a 16" carbine, is doing less than 900'sec. Fired at a dangling bowling pin, it takes out big chunks. Fired at a dangling tie-plate at 90 yard, it makes that heavy plate swing more than a hit with 5.56. Took a deer some years ago, with a .45 Colt carbine, and a slightly warmer load. She was DRT.
Big, heavy bullets, at modest velocities, are serious stuff.
Moon
 
The one word answer is "SAAMI".

The reason takes more words, but worth learning.

Same applies to other cartridges like .38 Special.
 

What’s the limiting factor of 45 ACP?

The maximum average allowable chamber pressure.

(If it's SAAMI's fault, what about C.I.P.? Besides, SAAMI had absolutely nothing to do with setting the parameters of the .45 ACP case, not the case dimensions, capacity, pressure, bullet weights, velocity, nothing, so how could it be they're fault.)
 
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Because if you commercially produce and market something outside of SAAMI specs,
and a mishap occurs, the lawyers will eat your lunch. That's why.

CIP applies in Europe.
 
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