Scalloped Line & Dust Cover Alignment

[pjk9hp]

Another aspect of the High/Hipower slide variations (maybe not be noticeable too) is the front end scalloped cut alignment with respect to the frame’s dust cover end. The following photo samples from different forums showed how the milling process produced an output which will not be so desirable to a hipower “aficionado” if he really is a perfectionist. Although there was no opportunity to see each and every photo sample’s other side views, two Holy Grail High Powers (oval ejection port models with both side views shown) indicate, I should say, perfect alignment.

Does your High/Hipower have perfect alignment?


 

 

 

 



 









 

 



 

 

 

 

 

 

 



 

 

[CXM]

Not exactly on topic, but I noted with interest the engraving in the first photo commemorating Victory in Europe shows a column of German PzKw IV tanks, probably H or J models.

Also, thanks for the posting... intersting topic.

V/r

Chuck

[pjk9hp]

Dec 11, 2017 8:24:37 GMT -5 CXM said:

Not exactly on topic, but I noted with interest the engraving in the first photo commemorating Victory in Europe shows a column of German PzKw IV tanks, probably H or J models.

Also, thanks for the posting... intersting topic.

V/r

Chuck

Hi Chuck,

The source just mentioned "the entry of the allied troops in Belgium."
www.littlegun.be/arme%20belge/fn/a%20fn%20gp%20commemoratif%20gb.htm

Regards...

[abninftr]

The WWII commemorative models were reworked, military surplus Inglis-made No.2 pistols.

What we are seeing is most likely the results of something I've mentioned time and again on another forum, the cumulative effects engineering tolerance and dimension practice.

To explain briefly, there are what are called critical and non-critical tolerances and dimensions. Essentially, critical tolerances and dimensions are those that will affect proper fit and/or function. An example would be the respective geometry and size of a sear and hammer to ensure proper engagement and release to fire the pistol. Non-critical tolerances and dimensions obviously are those that do not affect proper fit or function. An example here is the radius and position of an external feature of the slide or frame. That said, it is obvious that non-critical tolerances almost always have much larger plus/minus (+/-) factors than critical tolerances.

So, let's say the specified tolerances for machining the front of the slide is to cut an X long flat, then a Y radius with tolerances of +/-2.0mm at an angle tolerance at 90 deg. +/- 5 deg., and a frame dust cover length of A from a given reference point (to ideally align with the slide radius) with say a tolerance of +5.0/-1.0mm. Given these hypothetical tolerances, one could end up with 7.0mm overlap if both the slide and frame were machined at the maximum (+) tolerance.

It is not aesthetically ideal by any road, but it is the reality of engineering and manufacturing practice today.

[jaypee]

Immensely interesting stuff, guys. I'm in awe for sure.

[pjk9hp]

Dec 11, 2017 14:53:43 GMT -5 abninftr said:

The WWII commemorative models were reworked, military surplus Inglis-made No.2 pistols.

What we are seeing is most likely the results of something I've mentioned time and again on another forum, the cumulative effects engineering tolerance and dimension practice.

To explain briefly, there are what are called critical and non-critical tolerances and dimensions. Essentially, critical tolerances and dimensions are those that will affect proper fit and/or function. An example would be the respective geometry and size of a sear and hammer to ensure proper engagement and release to fire the pistol. Non-critical tolerances and dimensions obviously are those that do not affect proper fit or function. An example here is the radius and position of an external feature of the slide or frame. That said, it is obvious that non-critical tolerances almost always have much larger plus/minus (+/-) factors than critical tolerances.

So, let's say the specified tolerances for machining the front of the slide is to cut an X long flat, then a Y radius with tolerances of +/-2.0mm at an angle tolerance at 90 deg. +/- 5 deg., and a frame dust cover length of A from a given reference point (to ideally align with the slide radius) with say a tolerance of +5.0/-1.0mm. Given these hypothetical tolerances, one could end up with 7.0mm overlap if both the slide and frame were machined at the maximum (+) tolerance.

It is not aesthetically ideal by any road, but it is the reality of engineering and manufacturing practice today.

Mate,

Please tell us how did you come into the conclusion that the piece is an Inglis-made No.2 pistol?  The source link showed the other views of the high power with "Browning, S.A. Herstal", the serial number is 245-series which is definitely not an Inglis serial number, and the certificate of identification clearly indicates assembly is done in Belgique  (Belgium). Perhaps you can identify for us any indication on the pistol that it is an Inglis origin.

Thanks and regards...
 

[abninftr]

PJK, I was wrong.

I will tell you there are two reasons why I thought it was an Inglis made pistol.

The first is that there is a US company that makes and sells various commemorative items, knives, firearms, etc. that produced a WWII commemorative pistol using No.2 Mk I* Pistols in the 1990s. Second, I saw the rear sight ramp in the first picture, which, not considering that the pistol might have tangent sight, mistook for a No.2 Mk. I* rear sight ramp.

When I had a secon look at the picture, I saw the legend, 'Made In Belgium" that I overlooked the first time.

[CXM]

Which brings up the point that Inglis HPs are not the only ones with the 'podium' rear sight base. India Arms makes theirs with that design too...

FWIW

Chuck