Recoil in XD 45 vs Sig P220 45 surprising results

[Doodle]

So a few weeks ago I posted the story that led to me acquiring my new XD45C. Long story short I shot my father in laws' XD45 and we both noticed that it recoiled less than my Sig P220 SAO.
Now when I say significantly less I mean a MARKED reduction compared to my beloved Sig, resulting in much better split times (perceived not measured) between rounds and a heck of a rapid fire group. It was one of those moments where I was expecting the lighter polymer gun to recoil heavier. It went bang and I went wow, it went bang, bang I said wow again, it went bang bang bang bang bang bang...you get the picture and resulted in a rapid fire group tearing the middle of the ten ring out of the target.
Well I have since traded that Sig P220 for an XD45C and streamlight TLR-1. I took that gun to the range and it did not dissapoint.

IMG_0417.JPGIMG_0418.JPG

I only got an answer a few days ago as to why the huge difference in perceived recoil from my local gun shop guy. It turns out the barrel axis on the XD is significantly lower than on the Sig, resulting in more energy coming straight back into my arm and body and less muzzle rise. Well I knew of this, but now I have experienced it and it was cool!
220-nitron-SAO-detail-L.jpgXD45Compact.jpg
Notice how much closer to barrel center line the web of your hand rides on the XD vs the Sig.

[DefensiveCarry.com]

[JOHNSMITH]

Interesting. Thanks for the report. What is more interesting is that among the "big three" polymers, the XD actually has the highest bore axis. I think the M&P has the lowest.

[ranburr]

The barrel sits about the same on an XD as it does in the Sig. The difference is the frame of the XD flexes. This gives you the perception of less felt recoil.

[Doodle]

The barrel sits about the same on an XD as it does in the Sig. The difference is the frame of the XD flexes. This gives you the perception of less felt recoil.

Uh I disagree you can actually see the difference in the pictures side by side pay particular attention to the rear of the frames where the top of the web of your hand ends up. Im sure flexing of the polymer helps.

Edit: I had to measure to see if your claim had any weight and I measured the striker indicator (in line with bore center) to be 7/8" above the top of my hand on the XD.(we'll be generous and call it an inch) Then I found a holster for the p220 that I haven't gotten rid of and measured from the bottom of the rail in the holster ( I gave it a little bit to allow for tolerances with in the holster) to where the the bore centerline would be.(also eyeballing) I came out with about 1.5 inches. I believe the bottom of the rail correspnds to about as high on the grip as your gonna get the web of your hand. Now the equation for torque (rotational force) is force X radius. This means that everything else being equal (differences in weight, grip angle, etc.) the sig will exibit 50% more recoil due to the bore height difference. Now I know my math a theory is sound but my measurements on the sig are a little inexact but I would bet I'm within an 1/8" or so.

220 height.JPGxd45 height.jpg

One last thing...if you have an M&P 45 or a Glock 45 do me a favor and measure from the top of the web of your hand to approximate bore center and post the results here. I'm curious how much difference there is between the big three polymer pistols. I also found that the bore height is a major subject of debate concerning the p220 when researching and trying to find measurements online.

[JohnLeVick]

The boreline of the XD is clearly lower than that of the Sig, and muzzle flip is therefore reduced. The reduction in muzzle flip is often perceived as a reduction in recoil, and as noted by someone above, the polymer frame helps a little. The XD does indeed have a higher boreline than some other poly pistols, like Glocks and M&P Smiths, but the high boreline and consequent muzzle flip of Sigs has always annoyed me. I don't perceive much more muzzle flip with my XDm .45 than I get with a 5" 1911, but there was sure a lot more with my Sig P220s, before I got out of the Sig business. The OP's results are really not the least bit surprising.

[Doodle]

The boreline of the XD is clearly lower than that of the Sig, and muzzle flip is therefore reduced. The reduction in muzzle flip is often perceived as a reduction in recoil, and as noted by someone above, the polymer frame helps a little. The XD does indeed have a higher boreline than some other poly pistols, like Glocks and M&P Smiths, but the high boreline and consequent muzzle flip of Sigs has always annoyed me. I don't perceive much more muzzle flip with my XDm .45 than I get with a 5" 1911, but there was sure a lot more with my Sig P220s, before I got out of the Sig business. The OP's results are really not the least bit surprising.

I have to say I was surprised, but this is the first time I have shot 2 guns of the same caliber back to back where such physics could be observed. I understand it I just did not realize I was a victim of it.

[JohnLeVick]

As Paul Harvey would say, "Now you know the rest of the story."

[Doodle]

I just read on a different forum the deifference in bore axis between the M&P and a comparable XD is <.2", can anyone substantiate this?