Fact or hogwash?

[GunreviewWebmaster]

I read recently an interesting hypothesis. From my knowledge, I don't know whether or not it is true. Here it goes:

There is a premise that semi-autos with inner slide rails are more inherently accurate than those with conventional outer slide rails. The Sig 210 and CZ 75 are used as classic examples. I don't see how inner slide rails could improve accuracy. But, I thought I'd put this out so that the expert gunsmiths on TFL could respond and explain it to me in simple English. Is there any truth to this myth? If so, please explain how inner slide rails are inherently more accurate.

[Stephen A. Camp]

Hello. I don't think that JUST having the internal rails would greatly increase accuracy in and of themselves. They do have the advantage of allowing for longer engagement surfaces. I own a SIG P210 and it IS extremely accurate out of the box. I own a CZ75 and it's quite accurate, but not in the P210's league. I own an accurized 1911 which has NOT had the slide-to-frame fit reduced via slide tightening, but a tighter bushing's been fitted. It'll shoot as good or better than the P210 as will my match 1911. The 1911s have slide rails outside the frame. What IS true is that if you get a malfunction with the P210 or CZ, it's a bit tougher to clear at speed due to less purchase on the slide when compared to a BHP, 1911, etc.

Best.

[BB]

Theyre stronger because there is more surface area contact between the slide and the frame. I've never heard of accuracy improvment because of it; but I will say this much: slide to frame fit [and or design] has zero to do with accuracy in a Browning-type semiauto pistol. Well, maybe thats a little strong; I think its around 5%. Barrel to slide fit is where the accuracy is. Maybe in a blowback pistol, since the sights are on the slide and the barrel is fixed to the frame would frame/slide fit and design come into play.

[Art Eatman]

Seems to me that for a pistol, the relationship of the sights to the centerline of the bore determines the inherent accuracy. From this, accuracy depends on the uniformity of lockup--without looseness--of the barrel and slide. As long as the motion of the hammer and the force of the spring does not affect the lockup between the barrel and slide, accuracy should be unaffected by "externals".

FWIW, Art

[C.R.Sam]

What Art and BB said.

Sam

[blades67]

My SIG Sauer "P" series pistols have full length rails, this helps with regards to accuracy, but the consistency of the barrel lock up is where your true accuracy comes from.

[Mark King]

I don't think it makes any difference whether or not the slide rides inside the frame or outside. Accuracy comes from precice fitting of the parts. You be sure that a $2500-$3500 Sig 210 will almost certianly out shoot any production 1911, but put it up against a high end Les Baer and the playing field is pretty much level. Would probably be up to the shooter. Both guns go through much more hand fitting than a normal production gun thus the increased accuracy. Other guns are manufactured to very close tolerances and are hand finished, thats why the CZs, Kimbers and Kahr pistols are known for better than average accuracy out of the box. They also have some of the best out of the box triggers too.

Just my $0.02

Mark / FL

[johnwill]

Hogwash.

[radom]

I agree on the Hogwash. Its just that the inside rail guns are fitted tighter out of the box with a tighter lockup.