Nick
Spike
Posts: 31 
|
Post by Nick on Mar 30, 2009 20:40:24 GMT -5
I am in the process of building another smokeless, but this time on a 700 short action, sabotless and a 45 cal. I am looking at using a Pacnor or a Rock Creek cut rifling barrel. Rock Creek has a little better lead time than Krieger, so willing to give them a try. I dont think you could go wrong with any of the major barrel players. If I go with a Rock Creek, Mike Rock will cut any twist and my choice of a 5 or 7 groove.
The barrel contour will be a #6 or Palma LT, which I have found both Pacnor and Rock Creek are very similiar measuring .75" at the muzzle. I would appreciate your thoughts on the 5 or 7 groove and the contour.
Nick
|
|
|
|
Post by smitty on Mar 30, 2009 20:57:58 GMT -5
Personally owning a Pacnor 45 barrel plus seeing & hearing of ALL the great results that so many others are getting with their Pacnor's makes me wonder what the advantage would be with a Rock Creek barrel ? And since Dave D has done all the leg work with Pacnor it makes ordering a barrel very simple and you can even get a breechplug from Pete to use 45 ACP pistol cases. Now that's hard to beat !
smitty
|
|
|
|
Post by tar12 on Mar 31, 2009 4:49:45 GMT -5
I believe pac-nor will do any contour you want.
|
|
|
|
Post by edge on Mar 31, 2009 7:21:46 GMT -5
If you go with a #6 custom Sporter barrel you might ask them the make the "D" dimension 4 inches instead of 3. It may just be me, but I would prefer the powder to be in the 1.200 section and not the transition. Even in the transition it will be larger than the Savage barrel, but I am a belt AND suspender guy  edge. |
|
|
|
Post by tar12 on Mar 31, 2009 11:07:56 GMT -5
If you go with a #6 custom Sporter barrel you might ask them the make the "D" dimension 4 inches instead of 3. It may just be me, but I would prefer the powder to be in the 1.200 section and not the transition. Even in the transition it will be larger than the Savage barrel, but I am a belt AND suspender guy edge. Excellent idea! |
|
|
|
Post by rossman40 on Mar 31, 2009 11:24:10 GMT -5
I agree with Edge on this. We haven't talked much on barrel contours and I think most are done close to a factory contour.  I too would like to see more meat in the chamber area. With a heavy varmint contour the "D" dimension is normally 4 or 5" where as some sporter contours it is only 2.5-3.5". I would have to do some calculations to work up a weight difference. There is no extra cost on the barrel contour but it again is one of those balancing acts. The heavier the barrel the more weight you have to carry, more stress on the action. |
|
|
|
Post by edge on Mar 31, 2009 12:16:39 GMT -5
I have slightly modified #7 Krieger and Shilen barrels. A Savage .458 built on a 110 action with scope is a bit over 12 1/2 pounds. edge. According to this chart the #6 would be about one pound lighter.  |
|
|
|
Post by rossman40 on Mar 31, 2009 16:01:16 GMT -5
But a #19 on your chart would only be 1/2 lb heavier and have more meat in the chamber area. IIRC the factory Savage 10ML barrel has basically the same contour as the varmint barrel which the "D" dimension ("B" on your chart) is only 2.5". Of course the barrel diameter is 1.065". With a Remington action the barrel diameter would be larger (1.250") then the Savage since you do not have the barrel nut to worry about so you would have more meat in the chamber area to start with.
Things to ponder!
Where does a barrel bulge most of the time?
What barrel contour has most of the Pacnors been done with?
Nick, the problem with shooting sabots is you have a 4 petal sabot and 5 or 7 lands. If you get a land in the cut between petals the petal may want to twist and/or you get uneven support of the saboted bullet. No concrete proof of this but I seemed to cut back on fliers once I started to index my sabots so that the rifling was equal on the petals. I wonder how much extra to go to 8 groove? Of course shooting sabotless none of the previous applies.
The thing with 5R or 5C (or an even older term "Enfield" back in 1885) rifling is that there will always be a odd number of lands/grooves. A land will be opposite a groove, instead of the bullet being squeezed between two lands the bullet material that is displaced by the land goes into the groove on the opposite side. The sides of the land is not 90 degrees but canted so the bullet isn't forced into a square corner. What the end result is less stress on the bullet and rifling, less friction which in turn becomes less fouling, a faster bullet in the bore and longer barrel life. This rifling that kinda faded away with the Enfield was brought back by the Russians (the R in 5R), for using with steel jacketed ammo, and resurrected here in the states by Boots Obermeyer (Mike Rock apprenticed with Boots). While this would be great for sabotless I do not think it maybe the best with sabots.
|
|
|
|
Post by tar12 on Mar 31, 2009 20:05:16 GMT -5
Excuse my ignorance but what do the numbers in the Sporter Barrel contours chart under the letter D stand for?
|
|
|
|
Post by Chris Champion on Mar 31, 2009 20:30:43 GMT -5
"D" = the length of barrel where the muzzle diameter = "C"
|
|
Nick
Spike
Posts: 31
|
Post by Nick on Mar 31, 2009 20:31:28 GMT -5
Edge & Rossman
I appreciate the feedback. What I am trying to accomplish is a little more barrel length, but with no more weight. I will most likely use the Pacnor with Petes / Edge design breach plug. The reason I was thinking about a cut rifling barrel is that I have had great success with the Krieger barrels, but simply do not want to wait 4 months. I am building this gun to shoot sabotless, but if accuracy is not to my expectations, I will have to start shooting saboted loads to get my desired accuracy. The use of a #6 contour was the contour that Richard from Richard Custom Rifles uses and the barrel is a Krieger #6 @30" on his custom smokeless rifles. He is very nice to speak with and will guarantee MOA to 600 yds, which caught my attention. He will only build 10 rifles a year and is booked untill sometime in 2010.
Thanks
|
|
|
|
Post by jims on Mar 31, 2009 21:05:20 GMT -5
nick: That is quite a guarantee. I do not plan to shoot at 600 yards but if my Krieger could do half that well at 600 yards I would be ecstatic. I think the wind becomes a very critical factor at those distances. One can build in the elevation but it is harder to control the wind.
Nonetheless impressive results if he can do that consistently.
|
|
|
|
Post by edge on Apr 1, 2009 8:42:23 GMT -5
nick,
I assume that you were discussing the accuracy of Richards centerfire rifles and NOT muzzleloader!
Assuming that I am right, I bet he chooses his contour based on the cartridge being used.
Your "cartridge" does not start at the bolt face as a centerfire would, your powder is pushed forward 1 3/8 from the bolt face!
Changing the 2.75 to 4 inches would only add a few ounces to the weight and would actually make a stiffer barrel.
A Sporter contour saves weight and a couple of ounces near the action should not hurt the balance nearly as much as a #7 or larger one does.
I would call Richard and explain you specific conditions and see if he would add the extra length. If you want a sketch of the breechplug in the barrel I can PM or email it.
edge.
|
|
|
|
Post by edge on Apr 1, 2009 9:02:38 GMT -5
|
|
|
|
Post by rossman40 on Apr 1, 2009 9:10:21 GMT -5
Again me and Edge are thinking alike. If you went with the #6 sporter contour and stretch the "B" dimension (in the chart Edge posted) to 4.75" and the "F" dimension to 8" you would gain a lot of meat in the chamber area with little weight added. It would also be enough that if you did bulge the barrel in the chamber area you could set back the barrel as a few members have done.
The sporter contour, which could be called a radiused (sometimes called a Douglas taper) or double taper, strength wise I would ask if it was radiused or tapered and go with a double taper. Most barrel makers go with the Douglas method and use like a 30" radius.
Lija barrels does have a calculator on their website to come up with a more exact weight.
|
|
|
|
Post by screwbolts on Apr 2, 2009 8:03:15 GMT -5
This is a great thread with great definitions and explanations! Along with tons of good accurate info!!! :-))
Ken
|
|
Nick
Spike
Posts: 31
|
Post by Nick on Apr 2, 2009 23:04:20 GMT -5
The following is richards website. If these rifles can perform what he claims, they have my attention. He is a custom gun builder, but is limiting is work to 10 guns a year, as he is trying to retire. I purchased his CD and he told me that the CD will cover building his smokeless from start to finish. He is using shortened 308 cases for ignition and the breachplug he uses are Knight breach and niple. Very genuine guy to speak too. Thanks www.richardscustomrifles.com/custommuzzleloader |
|
