Low Bore Axis 9mm.

[ugaarguy]

I think the new Steyr M1A series looks fantastic, I've said it before but I'd really love to see a gun with a low bore axis like that also use a rotating barrel system like the PX4. I think such a gun would be a very soft shooter.

I think a conversion is possible, and wouldn't be difficult. The CZ 24, the rotating bbl design I'm most familiar with, uses a small block to engage the bbl for lockup. The block is held in by the takedown catch, so it being seperate from the frame allows the pistol to be dissasembled. If you could design a block to be held by either a take down latch like on a Glock, or lever/pin like on others then you could move on to the bbl. For the bbl all you'd need is a diagonal lug to meet a matching groove on the block, or vice versa, and the basics are there. The only other thing I'd do is add a bushing at the muzzle, or a bushing held in a small block within the slide, to support the bbl since rotating lug alone doesn't quite provide the same stability as the tilting lugs. Since it would be a conversion from a tilt breech design the bore wouldn't be as low as it could be if made that way from the ground up, but it would help counter muzzle flip since the bbl is no longer tilting up to unlock under recoil. Still on something with a low bore axis like a Glock or Steyr such a conversion could make for even sweeter shooting. If you could machine the muzzle end of the slide to take a bbl support bushing then using a large bushing made from a dense metal like tungsten would even further reduce felt recoil affects, as long as the slide didn't get too heavy for standard ammo to cycle the action. Anyway, I think it's do-able.

 

[CraCZ]

Ditto to what ccw9mm said. All the CZs have a very low flip. With the slide being internal to the frame you can place both thumbs high on the frame which helps some too.

 

[bg226]

In 9mm, I haven't noticed a difference when it comes to bore axis.

I have noticed significant muzzle flip in 9mm with high bore axis. Some say technique trumps low bore axis. All being equal, lower bore axis results in less muzzle flip.

 

[JohnKSa]

The bore axis on the 9mm PX4 is about a quarter inch higher than the Glock 17 bore axis.

Kind of interesting, to read Beretta's commentary about the Browning tilting barrel system requiring space under the barrel for locking mechanisms. It sounds pretty good until you take the PX4 apart and realize that they put the "central block" underneath the barrel. It appears to be a wash to me.

(The "central block" is the part that controls the barrel's rotation during slide motion.)

 

[ugaarguy]

JohnKSa, thanks for the info, I now know not to trust anyone to execute a design correctly, even a major player like Beretta. If only they'd fully maxamized the rotating bbl concept.

 

[JohnKSa]

Well, I'm not really saying anything negative about the design--I was just pointing out that there's pretty much the same amount of mechanism under either action type (at least as implemented in the two pistols I was comparing.)

The PX4 is a nice pistol and my wife says it has less felt recoil than a Glock 17. I can't tell the difference.

 

[JohnEP]

Many factors determine percieved recoil and muzzle flip.

I agree with SteveS, hkusp, and albanian. Many factors determine percieved recoil and muzzle flip.

I purchased the Steyr S9 exactly b/c of the low bore axis, believing it would minimize flip. I now realize that light-weight polymer frames offer very little inertia to counteract the slide. I now believe that the weight of the frame, and the quality of your grip matter more. At my CPL class, my instructor let my wife and I shoot his 1911 .45ACP. Our experience is mostly 9mm, but we had no complaints with 'muzzle flip' on that .45 pistol. She knocked down all the standing targets w/o a miss (controlled rapid fire), and I finished off the discs downrange, on first go with that caliber. For comfort, muzzle flip, and speed to next shot, I'd rather fire his .45 than our 380acp Walther PPK/S.

As a relative newcomer to this sport myself, let me suggest that you go to a range and rent as many pistols as you can. Ask to hold several to see how you like the grip before you pick one to rent. Some ranges will allow you to save your rental fee reciepts toward the purchase of a pistol.

Of the pistols we own, my wife and I like the Steyr S9 the best.
See my review and range repot here:
http://www.thehighroad.org/showthread.php?t=213940

I believe the Steyr MA1 should be a great pistol, but check others out before your are enamored with some 'spec' such as low bore axis.

John

 

[ugaarguy]

Well John(KSa) I guess she may be more sensitive to muzzle flip and perhaps the strait back recoil is easier on her wrist. I guess my comments were a bit negative on the PX4. When i say execute the design correctly I mean not only make it reliable, but take advantage of the potential to seat the bore lower in the frame by moving the block forward. Who knows, maybe they'll tweak the design.

Edited to clarify which John. Also, good post JohnEP, and welcome to THR.