Tech Wisdom: The Physics of Recoil

Tech Wisdom: The Physics of Recoil

Before the election, I had stocked up on some ammo just in case internet sales were abolished, which thankfully did not happen. I enjoy shooting my 1911 chambered in .45 ACP, but more with a lighter 185-grain target load as opposed to the 230-grain hardball. I came across an online sale for some non-toxic Winchester Super Clean ammunition, which is loaded with 165-grain FMJ lead-free bullets. So, I bought a case of this ammunition, thinking that this should be a nice-shooting load with even less recoil than my 185-grain target loads. Surprisingly, the boxes that arrived were labeled for 160-grain bullets, not the 165 grains in the ad.

When I shot this ammunition at the range, the felt recoil was not too intense, but when the slide cycled it seemed as if it was going to fly off the back of the gun. The velocity on the box seemed a bit above normal at 1,100 fps. I only put 100 rounds downrange, afraid I was going to destroy my gun. Since then, I have bought a couple of heavier recoil springs to try so I can shoot this ammo. I have not yet tested them, though. Can a five-grain difference cause this?

I do not know if I am incorrect in expecting a lighter load to shoot better with less recoil, but I definitely do not want to make this mistake again and get stuck with ammo I do not even want to shoot. Can you possibly explain where I went wrong here? I normally buy 50-round boxes until I find ammo that I like. This time though, I jumped on a sale price, only to regret that decision.
Joe Pagano, via e-mail


There are several answers to your question along with a little guidance as to how hopefully not to find yourself in a similar situation in the future.

First, you need to understand that felt recoil in any firearm is a product of multiple factors, not just bullet weight alone. Velocity of the bullet is a prime contributor to the recoil generated by a cartridge. In this case, the velocity of the bargain ammunition was several hundred feet per second faster than your 185-grain target load.

Next, you need to consider the application of the ammunition that you are buying. Usually there is a description on the box as to the intended purpose of the ammunition.

For example, factory loaded, standard-pressure .45 ACP 185-grain ammunition is rated from 770 fps on the low end to in excess of 1,000 fps on the high end.

The application of the 770 fps loads is to punch holes in paper at 25 and 50 yards on a precision-pistol target range. As velocity increases, so does the ammunition’s purpose. The application of the 1,000 fps and beyond loads is generally for punching holes in living tissue for hunting or personal defense.

In the middle of the high and low ends of the .45 ACP, 185-grain loads are what is referred to as training ammunition. Training ammo is typically considered target fodder because of its general use on a variety of target materials from plastic to paper to metal. It is loaded to velocities in the 900 fps range in an effort for it to function in the greatest variety of .45 ACP handguns.

This load also comes close to duplicating the felt recoil from the original, industry-standard 230-grain FMJ hardball load traveling slightly faster than 800 fps.

All that said, in reading the information on the cartridge box, it stated that the ammunition was for training in lead-free environments specifically, but could be used elsewhere as well. This would indicate to the user that this ammo should function in any .45 ACP pistol in a training environment.

A 165-grain bullet traveling at 1,100 fps as stated on the cartridge box puts the felt recoil in the neighborhood of the 230-grain hardball round, pretty much where it should be. But, the boxes held 160-grain bullets

The lesson here is to read the website’s description of the ammo without adding interpretation before buying. The online sale advertised 165-grain ammunition, but the boxes were labeled 160-grain. That’s a good example of why buying a single box of a new (to you) load is always a good idea before committing to a full case.

I like to get a good deal as much as the next guy, but it is important to see the big picture before committing your hard-earned money. Asking a simple question can save a lot of heartburn in the long run.

Your gun should handle the ammunition you purchased without a problem utilizing a recoil spring compatible with the standard 230-grain FMJ cartridge.

Always remember that felt recoil is a subjective phenomenon that is oftentimes as much between someone’s ears as it is between their hands.

If you do not care for the ammunition, get rid of it, trade it or sell it to someone who wants it and chalk it up to lessons learned.

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