i see that a lot of guns use a barrel clamp that has bolts to hold the clamp on the barrel.i thought that this clamping type put a strain on the barrel and made it shoot bad groups.i was going buy a article by sinclare that he states a compression is put on the inside of the barrel that is not good for small groups.
The majority of rail guns today utilize a v block or a round channel with a Delrin sleeve. The Delrin helps to isolate any resonant vibrations created in a traditional metal to metal fit, commonly seen in the v block. I have seen several methods for utilizing Delrin, solid Delrin sleeve, split Delrin sleeve and a 3 piece Delrin sleeve spaced evenly in the block. The guys using these Delrin sleeves rail guns shoot extremely well. As far as fastening the v block there are typically 8-10 bolts that are torqued down and while conventional wisdom would leave one to believe that torquing imparts a strains equally across the barrel, with a 1.350 diameter barrel I don't think that occurs.
At the Nationals, I saw Rail Guns with some type of non metallic sleeve isolating the barrel shoot vey well, and some with just a standard V-Block, shoot very well.
I also saw Rail Guns with some type of non metallic sleeve isolating the barrel shoot poorly, and I also saw some with just a standard V-Block shoot poorly.
This I know or a fact. Whether you are using a Sleeve, , or just a V-Block, you CAN close the ID of a barrel with too much torque on the bolts.
I proved this to myself by taking a barrel blank and finding the deltronic Pin that would just slip in, and then seeing at what point I could tighten the ten 5/16 clamping bolts so that it would no longer slip in.
It makes no difference whether you have a non metallic sleeve isolating the barrel, or a V-Block. At some point just north of 100 inch pounds of torque, the ID of the 1.450 diameter barrel collapsed enough to where you could physically measure the closure with Deltronic Pins.
Will this affect the accuracy potential of the barrel. I have proven to myself, at the range, that the answer is yes.
I torque mine to about 50 inch pounds.
Last edited by jackie schmidt; 10-30-2016 at 11:13 AM.
Interesting and valuable information.
In your experiment, did the collapsed barrel spring back when torque was released? Or was the deformation permanent?
When I released the tightness of the bolts, the Deltronic Pin would slip in as before.
Originally Posted by NezRongero
Since I have Deltronic Pins in .0001 increments, I could probably do a video showing this. I have the 4 inch long piece of 1.450 unlimited barrel.
so i gather as long as the bolts are tightened a specifice amount you are safe.
what do others torque the barrels at andhow is this done.
I see in some 1000 yard guns they glue the barrel in a sleeve.but I like the idea that I can unclamp the barrel and switch out the barrel or the barreled action buy unbolting the clamps.
Build a rail gun that shoots well and forget about the "easy" barrel change. The concept you mention sounds good...but it ain't. The easiest barrel change I've ever seen was where the action was bedded to the rail and all you had to do was screw out the barrel and screw in another. That rail shot VERY well (as good as any)...but the barrel never was changed. Just sayin' !!
Keith Gantt was the owner of that gun and when he bought it I was thinking he wouldn't like it because it was a Remington action, right bolt, right port and because the action was encased it I thought it would be somewhat difficult to load. I was wrong on all accounts because Keith learned to shoot it as fast as any and won quite frequently. The only thing that was aggravating about that rail was the rolling case it came in....took up half a Caravan just to haul it around.