Secrets Of The Houston Warehouse

L

Louis.J

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With the extreme results Virgil achieved is there a reason no one is barreling in the same manor as mentioned below?

The three jointly conceived the idea of undercutting a 45-degree slope on the inside edge of the receiver ring, leaving about two-thirds of the receiver shoulder untouched and square. Another 45-degree slope, cut farther inside the receiver (on a Cooper action), terminated at the locking lugs. With the barrel precisely cut to snug up against the two sloped areas, as well as the receiver shoulder, perfect barrel centering became absolute and positive.

J.Louis
 
I would have to guess that the challenge presented by making the three desired contact points touch at exactly the same point of rotation might be why. BTW, did any of the magic rifles that shot so repeatedly well in the warehouse distinguish themselves out in the real world?
 
Good question Boyd a list of names was not provided in regards to who used the facility so one could only hope that someone in the know would chime in. It appears that more than one prominent bench rest shooter tested there.

J.Louis
 
Wasn't exactly the same, but the Gilkes action set up using a lot of 45-degree angles. Shoulder, locking lugs, etc were all 45 degree surfaces. There was a couple being used at Hawks Ridge 1K BR. Hard to determine the headspace, and didn't seem to win any more that conventional designs.
 
In any typical action, I cannot see were equal surface area could be found for an internal shoulder and receiver face. Since
that is unlikely, compression would never be equal. The other side of this and as AL states in a different way, is you cannot
both stretch and compress a barrel tenon.
 
Boyd Allen said:
I would have to guess that the challenge presented by making the three desired contact points touch at exactly the same point of rotation might be why.
Click to expand...

I agree. But I still think the concept is a good one. If threads locked up so consistently, then why aren't they used in milling machine spindles, lathe tailstocks, etc.? OK, there are other factors, but note that these machine tool connections use a very shallow taper, which gives very accurate x,y location and two-axis rotational constraints. More support than a short 45 degree angle. A half inch of threads at the end of a couple inches of shallow taper would sure make a secure connection between barrel and action. But that's much longer than most tenons. And I wouldn't try this in an aluminum action because the differential thermal expansion would be a problem over that long a length. Actually, I'd bet someone has tried this before.

Cheers,
Keith
 
No doub't it has bben tried. Back quite a few years ago, I asked Ferris Pindell how best to fit a barrel to a mauser action.
He replied that it would be near impossible to seat a barrel on both the internal and external shoulders. That he had tried.
That came from a way more savy guy than me.
 
Actually, the issue isn't whether the barrel is precisely in the center of the action threads, or even that I goes back in exactly the same place each time it is removed and replaced, but rather whether it stays put from shot to shot.
 
In the Houston warehouse story its somewhat ex[lained how the action and barrel threads were lapped together. When you
consider that some lead screws may not be perfect or may be worn in some spots, Its hard to believe that all barrel tenon's
have perfectly uniform threads. I might also add, that not all lathes will cut a perfectly perpendicular shoulder. Things must
be verified
 
What prompted me to ask the question is there was a Gentleman in Arizona who was developing a new single shot rifle called the DunLyon and the mating surface of the barrel to the reciever had a very short and shallow taper on the proto type and I thought this approach might have been a tad ahead of its time. When I first looked at it the means of attachment appeared to be a very simple and common since approach. Bob it did indeed make me think along the lines of a morse taper and a machinest friend and fellow competitor from out of town borrowed the article and when I get it back I can try to post a picture of it.

J.Louis
 
Boyd Allen said:
Actually, the issue isn't whether the barrel is precisely in the center of the action threads, or even that I goes back in exactly the same place each time it is removed and replaced, but rather whether it stays put from shot to shot.
Click to expand...

While I agree that shot to shot consistency is fundamentally necessary, alignment of the barrel with the action and stock center of gravity, and having symmetrical stiffness, is desirable to minimize excitement of horizontal vibration. If the tapered connection ensures alignment, it could be worthwhile, even if it is no more consistent than threads.

Cheers,
Keith
 
I have fit several Gilkes rifles along with an RPA Quad, a Grizzly and a Savage target action over a short period with each owner competing against the other. The Gilkes is no more difficult to fit then any other action, including the head spacing of it. The Gilkes only has one 45 degree angle on it near the chamber face and as you torque it the barrel threads are pushing rather then pulling on the tenon. The Gilkes has a longer thread then most other actions and if the thread fits correctly I don't see an issue with it.

I metioned the other actions because over the season each has won matches at 600 yard and 1000 yard competitions and the difference in score has been 2 points accross the four rifles. It was the shooters, not the rifles. The two Gilkes rifles were barrel block mounted while the others were conventionally fit in the stocks.

I would not attempt to seat on two surfaces unless one was a barrel nut and I'm not sure what that would do for you. It would be interesting to see how a rim-fire would do using the same method as the Gilkes. I wonder if it makes a difference because the Gilkes is barrel block mounted having the receiver floated.

Jeffrey
 
Jeffrey --

How do you set the head clearance on a Gilkes (aside from cut-and-fit with a go-gauge)? I really am curious.

I *think* I know where you are going with the Gilkes & rimfires. It is still going to depend on how long the tenon is, right? Of course, it can be pretty short.

I've long wanted to discuss rimfire actions/barrels with any eye towards designs specifically for benchrest competition, & thought about making some posts on the rimfire forum. It isn't a subject that interests the current people who post there. Perhaps the gunsmith forum is the best place.

If this cold keeps up & I have to sit out of work today, maybe I'll make a post here.

Charles
 
alinwa said:
Bob, is there a better way to verify square than to run past center, check the front cut against the back?

al
Click to expand...
AL, yes, you could face a large surface with the crossfeed locked , then retrace it with a good dial indicator.
If you have access to a good surface plate, you could also check by laying it on its newly faced surface with a dial . You
will be checking it for any rocking motion with the dial.
When retracing the facing operation with the dial, any error would be doubled and increasing past center.
 
Last edited:
Charles,

The Gilkes "shoulders up" just like any other action so you can use the same cut and try method as with any chamber reamer. I would like to try it on a rim-fire because of the small tenon diameter and the problems with putting a tight spot in the barrel just ahead of the chamber. It might be a solid set up. My rim-fire rifles are barrel block mounted and the Gilkes system would work well with a barrel block.

Jeff
 
Bob Kingsbury said:
AL, yes, you could face a large surface with the crossfeed locked , then retrace it with a good dial indicator.
If you have access to a good surface plate, you could also check by laying it on its newly faced surface with a dial . You
will be checking it for any rocking motion with the dial.
When retracing the facing operation with the dial, any error would be doubled and increasing past center.
Click to expand...
heres a few things on inspection 101 you never check a part in the same mach. it was machined in .as for using a surface plate and checking the rock in the part the correct way would be to place on 3 gage blocks the same size and indicate top and bottom.
 
George,, I must certainly agree with your 101 inspection rule, However, I know of no way for starters other than to veryfy
the machine your working with. Surface grinding a part simple duplicates the path of the machine for example, but top and bottom
may not be parallel. Facing a large surface can be full of what ifs. To indicate a part on 3 gage blocks is no doub't the best
way, but this kinda requires both top and bottom to be parallel. That in itself raises more questions. I'm not disagreeing with
you, just wondering how best to get there.
 
Bob, 3 gage blocks at 120 degrees at outer edges, you can check top then bottom if piece is really large i use a electronic gage amplifier with a long arm to reach to center. george
 
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