"Felt" recoil, and how you experience it

[Sevens]

Recoil can be measured with mathematics, but most of the calculators you can pull up on the 'net ask for the weight of the handgun and nothing else. These are good, solid numbers and they offer a point of evidence that can be a component in a discussion of felt recoil, but they still end up being just a discussion.

Not until you have the handgun in your hands, with your grip style, with whatever grips/stocks/finger rests installed on the gun, with it's barrel length & bore axis and all the OTHER myriad of components simply that make up the shooting platform -- can you decipher what you actually feel, and heck, that's to say NOTHING of the ammo you are feeding it, which is an obviously large component in the whole equation.

Why am I saying all this gobbledeegook? Well, range day today. The relevant player for this discussion was my EDC, a 10mm chambered Glock 29, Pearce Grip extensions on all magazines - and yeah, on this pistol, that's noteworthy. With nearly 4,000 documented rounds through this pistol, I can safely say that I'm familiar with it... how it shoots, how it feels, how it recoils.

The bulk of my shooting has been 180gr 10mm FMJ handloads. These loads average 1,060 FPS on my chrono. Recently, I bought a KKM .40 S&W barrel for this pistol and it runs my .40 S&W handloads flawlessly and I sent 200 of those down range toady. I haven't yet had the chance to chrono these loads, but were I a betting man, 950-975 FPS with a plated 180gr bullet is realistic.

I can't tell a difference in the felt recoil between the 10mm loads that are (likely) running a similar bullet 100 fps faster. This would be a BETTER discussion if I had true chrono data on the .40 S&W load, but I can safely say that it's a warm one.

I have two theories as to why they feel SO similar -- tell me what you think of them, or if you have any others that make sense.

1) the 10mm loads are short of it's full potential. I can run the same slug over 1,200 FPS without pressure issues, I just happen to have been using this load for a good long while at 1,060 average FPS. At this speed, these loads aren't running "full bore" 10mm pressure, which makes them a bit "mild." The .40 cal loads are likely running close to the acceptable & rational limit and THUS, the "felt recoil" is very, very similar.

I like that explanation, it sounds like I'm "thinking" about it.
But I'm wondering if it's much more simple, like #2 here:

2) I'm running a same-weight bullet only 100 fps slower and the BIGGEST component of the recoil that I feel with each shot is the EXACT same massive (though short) slide that is reciprocating with each shot. I'm feeling the slide mass and it's providing the recoil impulse more so than the ammo.

I don't own a .40 S&W chambered firearm. I don't care for them, but 600 rounds in -- I'm in love with this KKM .40 S&W chambered barrel in this pistol. It's as rock-solid as the pistol itself and it won't stop for any reason and it delivers slugs with a level of precision that absolutely belies it's 3.78" length. It's worth every penny of the $175 I spent on it.

The grand "goal" was to run my carry gun with .40 S&W handloads so I could spew brass without the slightest care. That's something I simply cannot do with 10mm and frankly, I haven't heard of anyone who can. My goal with the .40 cal handloads was to make them HARSH, to replicate 10mm ammo that I carry.

I think I've accomplished that, with very little effort, actually. It drops steel plates like they are terrified of me, and man, that's a helluva lot of fun.

How do YOU interpret YOUR felt recoil?

Maybe I should have titled this thread "I had 60 degrees and sunny on Thanksgiving, and THIS is how I spent it!"

[Hawg]

I don't try to interpret it, I just go with it.