glock 40 recoil spring options

[lagarto]

The mass of the G40 slide is greater than that of a stock G20. That should have  a positive effect on reducing the effect of the recoil. In essence,  you should not have to increase the the weight of the recoil spring as much or any at all for the same load that you were shooting in a G20.

You can calculate all this if you want to go to a little trouble.  However, my Lone Wolf G20 LS with their 6.02" barrel works fine with an 18# spring
and a solid SS captive rod. It is actually more comfortable to shoot and more accurate than the standard G20 with a 22# spring using the same load.

Don

[sqlbullet]

Here is the wonky thing...

I was gonna do the math on how the extra weight would impact slide velocity.  lagarto is spot on that you would expect that long slide to have a good bit more mass.

So, since I don't have one of each to weigh, I thought I would just look them up on Glocks website and subtract the mass of the G20 from the G40.

Shock...

The unloaded weight of the G20 is more than the empty weight of the G40, both Gen 4.  G20 Gen 4 is 870 grams, while the G40 Gen 4 MOS is 798 grams.

Apparently the G40 slide is narrower than the G20 slide, and their mass is nearly the same.

[jrod]

I got an email today from kkm. They said they are currently testing there g20 barrel in the 40 and they should have an answer shortly.

[lagarto]

Sqlbullet

That's interesting.

Since I have different site systems on my 20/20LS slides, I can't get a precise weight difference. I estimate that it is about 55 grams. I'm sending an Email to LW for the exact weight of each bare slide.

I've always assumed  that Glock used the 17# system on all Pre Gen 4 models  to make it functional  with a broad range of ammo.

What's your thinking on why  they do it?

[lagarto]

Got a reply from LWD. It's actually 40 grams difference.

Don

[Captain O]

There's no need to "gild the lilly". The springs you have are just fine.

[Dave84]

Here is the wonky thing...

I was gonna do the math on how the extra weight would impact slide velocity.  lagarto is spot on that you would expect that long slide to have a good bit more mass.

So, since I don't have one of each to weigh, I thought I would just look them up on Glocks website and subtract the mass of the G20 from the G40.

Shock...

The unloaded weight of the G20 is more than the empty weight of the G40, both Gen 4.  G20 Gen 4 is 870 grams, while the G40 Gen 4 MOS is 798 grams.

Apparently the G40 slide is narrower than the G20 slide, and their mass is nearly the same.

.                                                                                                                                                                             Are they still doing the slim slide? Thought they went back to the 10mm 45 width. Any owners let us know? Thx.

[sstewart]

subjectively, the slide width seems the same as my 29. (I don't have any other glocks) Just the 40 & 29.
I have my micrometer packed away. House for sale and a lot of reloading stuff is packed away. Sorry.

[Dave84]

Good to know. I don't think the 9mm width slide was doing too well with full 10mm. They've never changed the specs on their website. You can bet it actually does weigh more than a Glock 20.

[sep]

I just weighed my G40 without a magazine using my 50 lb digital fish scale. It weighed 2 lbs 2 oz. That's with a 6 inch KKM barrel, Zev Tech Fulcrum trigger, Dawson Precision sights and stainless steel Gen 4 RSA. Empty magazine weighs 3 oz.

Slide width just forward of the ejection port is 1.120.     

[sqlbullet]

What does just the slide weigh

[sep]

My slide with Dawson Precision sights (adjustable rear and fiber optic front) weighs 1 lb 6 ounces.

[sqlbullet]

Thanks.

Anyone have a G20 slide they can weigh and post the results?

[4949shooter]

Thanks.

Anyone have a G20 slide they can weigh and post the results?

Sqlbullet,

I weighed my G20 slide. It is 17.42 ounces.

[sqlbullet]

based on those two numbers, 17.4 oz for a G20 and 22 oz for a G40, the slide velocity would be right at 20% less when the bullet leaves the barrel.