Does Short-Slide, Big Grip = More Efficient Shooting?

[spitfiremac]

Hi all, I'd like to throw a thought I had today at the hive mind and see where it sticks...

When the Glock 19X came out, I was one of the sneerers... the "Have they lost their minds?" crowd but now I'm questioning some of the conventional logic on long-slide race guns.

Mainly this... Does the lighter reciprocating mass of the shorter slide and the greater inert mass of the larger grip and magazine improve the flatness/anti-climb properties of the pistol over a conventional long-slide race gun? I'm thinking it might, but I don't have to be right on this, I'm just hoping for a good, dare-I-say-friendly discussion and hopefully a general consensus.

Let's start with what we know:

Long slide = long barrel = faster bullet & gases = more recoil BUT ALSO = possibly less unburnt propellant causing a softer blowback force

Long slide also = longer sight radius = more accurate sighting/shooting at distance = MAYBE also slightly slower shooting especially at near targets

Okay, so two things to deliberate here: How does the more unburnt powder affect recoil? Is a longer, more precise sight radius, also slower to sight in?

These are important in that these long-slide qualities could mitigate whatever advantage a short slide might bring to perceived recoil and follow up shots. Let's get back to that original question then... given that the slide mass reciprocates back on the user until a hard stop, and then back forward until another hard stop, all above a shooter's hand wouldn't it make sense to shorten it, giving it both less mass and leverage? You could even keep a long barrel and sight radius (mount the front sight high on the barrel.)

If there's an advantage I'd feel it would be the lessened mass of the slide, but also, consider a large grip and magazine. It would seem to me, magazine or not, that any stationary mass you could add to the frame/grip would help to dampen the forces pulling your hand back and up. Generally you want that weight to be forward, thus the barrel weights ala John Wick's P30... but any mass at all would still help, right? And a mag can't be consistent as you expend its contents down range, but any weight would still add to that inertia.

Whether there's something to that or not, we already know that a shorter slide area is anecdotally reported by many shooters as marginally preferable for fast handling and transitions to target, so that's a plus... as well as it's more convenient and usable for people in and out of really cramped spaces, so that rounds out the advantages that shorter slides, longer grips.

I think all those advantages don't meet up with the logistical and discretionary disadvantages of it in CC, but that's more personal lifestyle/preference. I'm starting to think that weird arrangement would make for a faster/flatter shooting gun, even if the bullets are neither faster or flatter.

[chris in va]

Heck of a first post.

[74A95]

Some of your premises might be wrong.

The longer the barrel, the lower the gas pressure at the muzzle when the bullet exits.

Data from QuickLOAD, 9mm Luger, 124 grain bullet, 8.0 grains of Accurate #7 powder.

5” barrel
velocity = 1220
gas pressure at muzzle = 4548 psi
% powder burned = 75.22%

4” barrel
velocity = 1157 fps
gas pressure at muzzle = 5808 psi
% powder burned = 72.44%


The difference in burned powder is just 3%
The difference in gas pressure is 28%

In general, gas pressure contributes to the recoil force via Newton’s law of every action causes an equal reaction. The higher gas pressure in the 4” barrel should contribute a larger percent to recoil force than the lower gas pressure from the 5” barrel.

While people talk a lot about the amount of unburned powder being a factor in recoil, in reality it might not matter. What does matter, I suspect, is the gas pressure at the muzzle, regardless of whether the powder is all burned or not.

[spitfiremac]

Great reply 74A95... now we're cooking.

Shorter barrel = higher gas pressure = greater recoil force

DONE

So a shorter barrel would contribute to recoil forces to a variable extent.

The question is whether or not that would be enough to mitigate the advantage that the lighter mass of a smaller slide could bring?

Even if it would, there's still the possibility of a longer barrel emerging from a smaller slide like a 5" or 6" from a Glock 19 or 26. Assuming you had the right ammo to cycle with those forces at play and maybe a red dot you'd still be good then, maybe flatter shooting.

It'd look stupid, but most gun trends do before they pick up.

I'm using 9mm Glocks for as a reference since they're basically the currency of the community now a days.

[Cheapshooter]

Voted maybe because if it does I doubt it is significant enough to notice

[imp]

My thoughts on the subject have nothing to do with slide weight or recoil, just that there is a benefit to a shorter sight radius.

The longer sight radius may lend itself to more accurate shooting, but a shorter one is faster to acquire. The difference between a 4 inch barrel and a 5 inch one may not be super easy to identify, but I've noticed a big difference when transitioning from a snub nosed revolver to a long barreled one. The front sight seems to swim around for a fraction of a second longer, resulting in slower split times.

[JohnKSa]

The weight difference between a G17 and a G19 (no ammo or magazine) is 0.89 ounces. Even if we assume that almost all of that weight difference is in the recoiling mass, it's still not a big change.

If you can find someone who owns a G19 with a threaded barrel, find a muzzle attachment that weighs about an ounce and then see if the gun shoots differently with and without the attachment.

Or maybe shoot a G19 side by side with a G19 that has a slide-mounted micro red dot.

[74A95]

Originally Posted by JohnKSa

If you can find someone who owns a G19 with a threaded barrel, find a muzzle attachment that weighs about an ounce and then see if the gun shoots differently with and without the attachment.

The longer threaded barrel might itself weigh an ounce more than the regular barrel.

[44 AMP]

Long slide = long barrel = faster bullet & gases = more recoil

I'm not so sure about all of that...

Long slide = long barrel, sure

= faster bullet, sure

= more recoil, not so sure.

Consider, same ammo, so same amount of energy available. Long slide & barrel = more mass. More mass will be different from less mass (short slide) once it gets moving but it also takes "longer" to get moving and moves slower.

And that can have an effect on FELT recoil.

Longer barrel usually means LESS recoil due to more weight. leave the slide completely out of it and shoot a revolver or single shot with the same ammo and a short vs long barrel. The longer barrel heavier gun recoils LESS.

Or stick with the autopistol. Shoot a Government model (5") and then shoot the same thing in an Officer's Model (3.5"). If you think the Govt model recoils more, I think you're crazy.

Yes, the math shows long barrels shoot faster, and faster means more energy and that energy means more recoil, BUT you aren't allowing for the weight of the longer barrel reducing the recoil effect despite the increased velocity. The mass of the longer barrel (and slide) literally "outweighs" the slight increase in recoil energy gained with the higher velocity obtained through the longer barrel.

The other point, about sight distance, longer does allow for more precision and that does take more time, but long or short sight radius can be used with the "flash sight picture" and I think any real difference in speed will be due to the individual shooter more than anything else.

[tallball]

To me, for revolvers and semi-autos in general, longer barrels seem to have less felt recoil.

It might have more to do with overall weight than anything else.

[dahermit]

More efficient shooting?

Longer slide = Longer barrel = longer sight radius = more accurate shooting?

[RickB]

I don't think there's one answer.
I've competed extensively with both a 3.5" .45 and a 6" .45, and my scores were dramatically better with the latter, but I was able to run lighter loads in the longslide, it also has better sights, etc., etc.; it would be difficult for most people to isolate only the length/weight/balance effects.

[spitfiremac]

Thank you all for your insight and experience.

It seems like the consensus is there might, repeat MIGHT, be validity to the idea that a lessened reciprocating mass would lead to marginally lessened force and recoil.

There also is clear consensus that whatever advantage this might provide is mitigated by the advantages of reduced recoil from the longer, heavier barrel providing consistent leverage forward and down.

It also seems that in general, we all agree that a longer sight radius is both more precise and ever so slightly slower to line up... both of which is close to a marginal shift.

Given this, there's no surprise that the competition market went where it went, with long slides, barrels, sights, and lightening cuts throughout.

[74A95]

Keep in mind that one of the reasons for slide weight reduction is to allow the recoil to reliably cycle the gun. A 9mm does not have that much recoil, and with a locked breech pistol, if the slide/barrel weighs too much, it won't cycle. That could contribute to why some of the long slide Glocks have the cutouts.

This is a big issue with building open class guns in 9mm and 38 Super. Adding the compensator significantly reduces recoil because of the extra barrel weight (longer barrel) and compensator. One purpose of the compensator is to reduce slide velocity, which it does very well, because the gases push forward on the comp baffles and this slows their rearward movement. Many times, the gun won't cycle with standard ammo, and only Major power factor ammo will reliably cycle the gun. This is also why many open class guns have their slide lightened. The slide, barrel and compensator combination is just to damn heavy to reliably cycle even with powerful ammo.

Open shooters also have to reduce the weight of their recoil and hammer springs for the same reason - they produce less resistance to slide movement. But if they reduce the recoil spring to much, the slide won't strip a round from the magazine. I built my own Open gun and you have to get al this stuff right to get the gun to run.

https://americanhandgunner.com/featu...ey-really-work

Lone Wolf 9mm compensators often come with a warning that some of their comps might not run reliably with standard ammo. It's because of the added weight and the effectiveness of the comp's design.

https://www.lonewolfdist.com/Detail.aspx?PROD=922040

[44 AMP]

Semi auto firearms are balancing acts. Slide/bolt mass, mass of other moving parts, spring tension, and other things are all calculated to use the available energy from recoil or gas pressure to operate the mechanism "hard" enough to function reliably, but not so hard it beats itself to death. Change any of these factors and the entire balance is changed. The pistols are designed and built to operate within a fairly narrow range of conditions when it comes to load levels. Inside its "envelope" they run pretty reliably. Out side that, not so much.

there are some parallels with motor vehicles, a duty pistol might be likened to a military truck made to run on multiple fuels acceptably well, and a match gun to a top fuel dragster, a specialized machine made to run on specialized fuel, only.

And like the engines in those examples, if you feed it something its not tuned for, it won't run right, and might even be dangerous. Knew a case where a guy got killed because he put jet fuel in his deuce and a half, saw my company commander limp his Duster back to main post running it on rifle bore cleaner too. (he planned poorly and ran out of gas and the bore cleaner was the only "fuel" available..car never did run right, after that, though ) If you put bio-diesel in your race car instead of what it was built to use, its unlikely you'll win the race...

[CDW4ME]

shot timer + guns to compare + same ammo = answer
(at least for that individual)

[pete2]

The answer, for me, is that a Steel Commander pistol is faster out of the holster than a 5" 1911. First shot is faster but it may or may not be as accurate for me. follow up shots may be slightly more accurate with the 5" gun. My opinion is that being a split second faster with that first shot makes the Commander a little better for carry. A lightweight Commander is my choice to carry for a 1911 gun. A Lightweight Commander length with the Officer's handle would be better for carry because it is easier to conceal but I like the full size handle.
My 2 cents for what it's worth.....................

[tipoc]

In reading through the original post I was a bit confused by the questions.

See the G19X is a gun with the slide of the G19 and the frame of the G17. The compact slide on the larger duty frame. The advantage is a few more rounds. Oh and the lanyard loop. The trade off being it's a bit harder to conceal and it weighs more than the G19.

The G17 slide (7.32") is a standard length slide while the G19 is compact (6.85"). A .470" difference.

The G19X, with a full magazine, weighs 31.39 oz.s vs. 30.16 for the G19.

The additional weight on the G19X will dampen recoil a bit but most shooters won't feel much difference in actual shooting. Well, except for those who prefer the longer grip frame.

In fact it's likely that the weight of the bullet, it's velocity, bullet construction and maker will cause more actual felt differences than much do to the increased weight of the frame.

None of the guns mentioned above are intentionally geared toward competition by the maker.

You will begin to see actual differences when using the G34 or the G17L both are geared towards competition. The sight radius is longer and the slides lightened.

tipoc

[Pops1085]

I wonder if it wouldn’t be more helpful when thinking about this to think in extremes and then drawing conclusions based on emperical evidence?

For example, I feel like this could be more understood if we thought about the difference between a 6-7” long slide 1911 in 45acp vs a 3” 1911 with a government sized frame like the Para Expert Carry? I feel like we could make some good conclusions if we looked at that and then scaled it down to smaller differences like 5” vs 4” Glocks. Just thinking out loud here. I have none of the aforementioned firearms but somebody must.

[Sharkbite]

Part of the recoil force is caused by the jet effect of the gasses blowing out the muzzle. They push towards the tgt and shove the gun back at the shooter.

That is how compensators work. By redirecting those gasses up and shoving the muzzle down.

I would think a shorter slide/barrel would make that worse

[K_Mac]

For me the physics are not really the issue. The shorter slide on a longer grip changes the balance and feel of the pistol. These are subjective differences that are going to vary from one person to the next. Which one works better for you?

I like the feel of a shorter slide to grip ratio, but I shoot a standard compact pistol better. Repetition is probably the real difference.