MBWT Data Comparisons (Damascus and Fluid)
 

Dr. Drew Hause and I have been sharing some thoughts about MBWT, especially thickness at the chamber/FC juncture. I decided to begin cataloguing my measurements to share with Dr. Hause. Thought some of you may be interested as well. I will add more as I build out the details.

Details:
- Measurements were completed using Hosford Barrel gauge and Skeets bore gauge
- I suspect #12 to have been altered (chambers lengthened)
- I found it especially interesting to see same gauge, different weight compared closely to see differences in thickness
- Another interesting point is the observation of the steep angle of the forcing cone in many of the Parkers

https://i.imgur.com/CabhsNo.png

Interesting stuff Dean. Have you ever seen the plotting graphs and charts Austin Hogan did on Parker chambers , bores and chokes?

I have several of them nd will post a few on another thread so as not to take your thread off on a different tangent.





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Reply
 

No, I have not had the opportunity to review those charts. I would like to see them.

Someone asked via PM my process for MBWT. MBWT = the minimum reading I get anywhere on the barrel. I take many measurements with the gauge and record the thinnest reading at any point. Further, nearly all my MBWT readings occur near a rib. This is also true for the 9" from muzzle reading.

That's not at all surprising given that the final/finish striking of the barrels was done after the ribs were laid.
This set of Grade-6 Damascus barrels not only are chamfered at the muzzles but you can easily see that the tubes are considerably thicker between the barrels and under the ribs and the striker, while maintaining the 'concentric' contour, must keep them thin while not going too thin.


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Very interesting Dean. Concerning the steep angle of the forcing cones you mentioned what length are you generally seeing on the cones? I assume the ones with the steep angles would be shorter possibly ?

On a side note of all the Parkers that I have measured that were original I have been extremely impressed with the craftsmanship in them and how concentric they were. The one exception would be a truly mint Remington era 16 gauge that has measurements all over the place. It makes me wonder if it was a Friday gun.

Randy,
I don’t document that measurement unless it presents longer than expected, but I would say 5/8-3/4 is the range where I see the nose of the cone. I should also like to confirm my statement as many, not all. When we see .010 or better in thickness change in a 3/4 inch travel....that is steep to me. On the other hand, other barrels in the sample only change a few thousandths. I only included one Parker where I believe the chamber has been lengthened.

I have had a different experience with concentricity. I find a good number of my original, maybe even mint Parkers to have inconsistencies in MBWT at the same longitudinal point.
Best,
Dean

Thanks Dean. I should clarify that when I was referring to Parker barrels as being very concentric I intended that to mean generally along the entire length and not at any one longitudinal point. At any one point I have seen the same inconsistencies that you have mentioned.

One gun I'd like to see more data on is a 16ga 0 frame. Larger bore, smaller frame= less wall.
I have one, and will attempt to get some meaningful numbers after the next coffee.

Edgar,
I would like you to share your numbers as well:)!

Your point is very valid and clear when you study like, original guns next to each other they provide for an interesting discussion. For example subjects 10 and 11. Both are original guns on a 1 frame (1 28" and 1 26"). The 28" weighs 5oz less than the 26". They have similar MBWT. Yet the 28" chamber/fc measurement is .020 less. One has a steep FC and the other a more gradual one of a few thousandths.

I should also add.....one is Meriden and one is Remington. A change of philosophy?

I have a few 0-frame 16’s as well including hammerless, a T/A hammer and a Lifter as well. I’ll try to get some measurements and post them here.

The Lifter has the Parker-made Laminated barrels.



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The 1907 Hunter Arms Chamber Specifications drawing shows the forcing cones as slightly less than 1/2" and a straight taper. The cone angle was shallower in the 1935 drawings with a length of about 5/8".

Austin Hogan stated that, at least early on, the Parker cones were cut at a Ogee rather than a simple taper; this illustration is obviously exaggerated. I've been looking for his posted WT numbers in my files without success.

http://pic20.picturetrail.com:80/VOL.../413955534.jpg

Was this cone profile continued throughout production?

Parker, 28" DHE 16ga. 0 frame, Made in 1898. Wgt 6/6
Damascus; Unstruck wgt 3/7, Finished wgt 2/12
MWT, .024"R, .024"L
MWT 9" from Breech, .046"R, .045"L
MWT 9" from Muzzle, .025"R, .024"L
MWT-Chamber, .095"R, .099"L
MWT-FC, .104"R, .107"L
Bore, .666"R (must be Satanic Steel), .665L

I'll double check these later, rule out my hand tremor.

Austin’s research also indicated the chokes were cut (or bored) at an ofee as well and he believed from the many Parkers he examined that this practice continued until Remington cut the chokes at an angle rather than continue the more precise and labor intensive practice of cutting them at an ogee. I don’t know if this also applies to the chambers/cones.






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I have a 1904 CHE 16 O-frame gun. It weighs a smidgeon over 6 lbs. (research letter also indicates this weight). The unstruck barrel weight is 3 lbs 1 oz. Actual weight is 2 lbs. 8 oz. Its barrel measurements (Hosford gauge for wall thickness measurements) are:

R/L:
Bore -- .666.,665
MWT @ Chamber -- .098/.092
MWT @ 9" from breech -- .040/.042
MWT @ 9" from muzzle -- .025/.033
MWT -- .025/.031

I had a complete set of Hayes’ choke reamers which were straight tapered.

Well there ya go.... again we disagree.

Can't argue with you on that point but neither can I argue with Austin's research data.....





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I wasn’t disagreeing with you. I merely said I had a set of James Hayes choke reamers which are straight tapered. They also are dated if I recall. The current custodian can confirm, if he wishes.

You sold those...? All of them, including the 8 gauge?





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I did not sell anything, and it did not include an 8ga. reamer.

More Information Added
 

Added finished barrel weights and tidied up some missing data points......

https://i.imgur.com/rZ2mEva.png

Austin was meticulous in his plotting of the measurements of chambers, bores and chokes he measured. Here he supports his findings of forcing cones and chokes having been cut to an Ogee.

I took these picture of some of the pages in his notebook. You'll notice that most of them are identified with serial numbers and some are right into the 1920's.


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I checked them out and can report back.

I have 15 factory choke reamers from various periods and for various gauges ranging 28g to 12g. (two of them are marked as being made by Hayes). 7 of them are finish reamers and the rest of roughers. The roughers are all straight tapers (checked with a straight edge). 2 of the finishers are straight as well. The other 5 finishers do have an ever so slight bow on the cutting edge. shaped like () if you will. The straight edge rocks just a hair.