A couple of questions for rail gun shooters

Boyd Allen

Active member
A very good friend has just started working with a rail gun that he picked up some time ago. It has a V style block that is about 10" long, and his current barrel length is 29". What have your experiences been in these areas? What length block do you prefer, and what barrel length? Thank you for your time.
Boyd
 
Boyd a lot of the top rail guns are still using the v-block set up. Theres been a lot of talk recently about Gary Ococks bushing on his rail and it deffinatly works well. I think he's using a phenolic shim between the block and barrel? but do a search on here and you should be able to find several post's pertaining to his setup. It would certainly be one worth trying to duplicate as his rail shoots as well as any ever built.
Best of luck and I hope he enjoy's the rail.
 
Thanks, but my friend is going to try his as is, with the V block, so I am still looking for block and barrel length info.
 
I understand, I have a RFD Rail, it has a 6" Aluminum V-Block, and a 24" 1.450 dia. Barrel, it shoots extremely well, it will put 10 bullets into one tiny hole when I do my part. I've seen quite a few with longer V-Blocks, just depends on who made the rail. Best of luck.
 
Shoot it like it is

I don’t believe there is a “favorite” design for a Rail Gun. I’ve seen a lot of Jay Young Rails at the Unlimited matches I’ve attended. In Fact, I own a Jay Young Rail. My first Rail was made by Clarence Hammonds.

I’ve also seen a variety of personal designs limited only to the imagination of the builder. Some with V-Blocks, some without. Design variety is a trade mark of the unlimited Rifle. A freedom of expression unlike any other Benchrest Class.

I am not a machinist,but I would guess that barrel length and V-Block length would depend on the overall design concept of the Rail Gun.

If it was me, I'd do just like your friend is doing.I’d take that Rail Gun out and shoot it like it is. Your Friend may like it ”As is”. But that’s just my way of thinking.



Glenn
 
A V block works just fine as long as you torque it down correctly. The problem is that everyone has a different idea as to the correct torque.
 
So, what is the correct method of torquing the screws in the V-block style of UL guns? similar to engine heads? Start in the middle and then out to the ends? Same torque on all the screws?
 
The way that I like to do it is start in the middle and alternate sets of bolts until I am at the ends. 27 inch pounds does the trick for me.
 
My Powell has a V-block, I torque it to 60 in-lbs I believe (per the original handwritten instructions I have somewhere). My contribution to the art is to lay a single narrow strip of that 10mil Poly tape along the three contact points in the block.

I've used barrels from 25" to 29"... all shot well. The best so far was the first Bartlein I put on it. 6000+ rounds, and it still shot two 10-shot groups in the .1s a month ago.

You can tune a rail barrel a little by sliding it forward or back in the block. This can be limited by where the trigger hangs in the guard but can affect how it shoots.

I built a Begg's style tuner for mine, 7/16 thick, 2.75 in diameter. It is effective as well.

Rod
 
If Possible,Contact the Builder

IMO,there's no better source of information about Rail Guns than the person who built it. When I identified the builder of the First Rail Gun I purchased, I called Him. Clarence Hammonds told me some things about my Rail Gun that I would never have known. If the builder can be contacted,its at least worth a phone call.



Glenn
 
If it is a good rail, Dwight told me to pay attention to the torque of the block. If I remember right, start at 40 inch pounds and go up to 80 inch pounds is 5 inch pound increments. You'll find where your block likes to be torqued....really made a difference and is generally repeatable between barrels.

Hovis
 
The only really, really, really good rail barrel I had was machined to fit and held in a round hole block accompanied by delrin. I can't remember clearly but I believe it was "bedded" in delrin using release agent on the block and barrel. I do know that James Messer worked all day on it and charged me peanuts. Mickey Coleman made me a "V" block and while it could have been anything - the rail didn't shoot as well after that change...ever. I got beat by those with similar blocks so it's not at all conclusive.

Cub Cooper said that you can sorta tune a rail by the placement of the barrel in the block - I agree.

Another thing...if it's not a good barrel it doesn't really matter what you do.
 
This has turned into a really informative thread, at least for me. The rest of you probably already knew this stuff.
 
I understand, I have a RFD Rail, it has a 6" Aluminum V-Block, and a 24" 1.450 dia. Barrel, it shoots extremely well, it will put 10 bullets into one tiny hole when I do my part. I've seen quite a few with longer V-Blocks, just depends on who made the rail. Best of luck.

I am using a 1.350 dia. barrel 24" long torqued to 40 in/lbs on my RFD Rail. It is a V block 6" long also.
Start at 25 in./lbs and work up to 40 in 5 in/lbs increments starting in the center an working outward.
If my memory serves me right, that's the way Bob Dodd told me to do it.

Gene
 
I have just started playing with my rail this last week. This is my first real attempt with a rail gun, and my experience so far has been positive.
I chambered a 13.5 twist Shilen, and man oh man, is this barrel a shooter. My barrel is 29.5 inches long. Most would say that is to long, and I would probably agree. However mine is shooting so well I hate to change it. My barrel block is a V type with a flat on the top piece. My block has 12 bolts and has to be close to 10 inches long. Its a big old block!! I torqued my bolts down to 35 inch pounds, and ran with it. Seems to be just fine.
I haven't shot my rail at 200 yards yet, hopefully it will cool down a pinch this week so I can. My 100 yard groups are really really small, I just hope that hold at 200. Lots of fun though. I wasn't sure I would really like a rail, but I must say I am enjoying it very much. Lee
 
While we're here...

What's going on these days concerning how you set the rail on the bench. Sticky feet, nail it down, or both depending on where you are?

Also, please mention how the rail has to be handled when using sticky feet.
 
Back
Top