.257 QUESTIONS!
Good day all- I have a few questions about a .257 build… What would be a good barrel length to use? I’d like to keep the rifle handy, and it’s going to be shrouded… Im thinking anywhere between 24″-28″ would be okay. I’m of course going with a TJ liner, but which one do I get? the 1:14″ or the 1:10″ twist? Would 1000 cc’s be alright? I’m going to have two 500 cc tanks linked together. They’re both 3k psi though… would this be a alright set up? I know most of you guys building on a AF rifle are using the larger 4.5k tanks, so I wasn’t sure. Thoughts??
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I didn’t really want to use an FX platform anyway… It will probably be a long time before Chip does another run of Sumo’s, if ever… Any Ideas on how to make an AF Condor-like body that won’t be heinously expensive?? I don’t want it to be a tube with a scope rail and trigger area like stock- I’m thinking thicker, with angles, same I.D. though- I don’t want any crazy custom internal parts… the gun’s fine- I just don’t like the body. I want to use most of what is available for this series of gun… the overall look I’m after is the MSR, but I don’t need to copy every angle… I’m just looking for the overall look… and to raise the rigidity of the AF body. and incorporate things that would possibly be needed, like an angled M1913 Rail, and single side (right) feeding… Thoughts??
Just for reference, the Remington MSR… if you squint, it sorta looks like a condor w/Tony’s tank adapter…
Hmmm… I was thinking more along the lines of having a 68 cu in 4500 psi tank attached via remote line to the standard AF tank, using Tony’s dropped tank adapter. I would just plug the gauge hole. Or would it be better to keep a gauge on the adapter, and a gauge on the larger tank? Not sure how to read a setup like that… Thoughts? I’d like to be able to “conveniently” carry the rifle. The 68/4500 tank would be in a pouch on my back. Again, thoughts? That should give me plenty of air for a decent amount of shots (20?).
Old goat is trying to get the Boss 30 converted to 257, he does not seem to think it will shoot the heavier slugs very fast.
The Boss is more like the Royale I think which has a solid bolt I believe, the Elite has a hollow bolt with the air flowing through the bolt, I doubt it can work for what your wanting to do.
There are also the Korean guns, they get around 800 with the 257420.
Your best bet would be a AF platform and one of Doug’s valves and have a TJ barrel fit.
You can still do the 1000 cc with the AF Platform by putting a Etac or one of Tony’s off set adapters on the main bottle, remove the gauge and have a double nipple set up. Attach a 2nd bottle where the forearm is and have a custom etac made up that has a fitting that allows you to run a line from one etac to the other bottle. There are several ways to attach that tank under the forearm as it already has a rail attached to it.
RC
Anyone with experience with the FX line of rifles- specifically the Elite, can it be pumped up enough to shoot a .257 70+ grainer? Air shouldn’t be a problem…
Yep! Earnie, AKA 220 swift is the man for the double tube work. The man does fantastic work!
KnifeMaker
SWEEEEEET!!!!! thanks for the words of encouragement Roach!! I can’t wait to build it!! Actually, this rifle will have a stock that will use an AR pistol grip, a PRS stock, and mount a bipod… I guess like an F-Class rifle: bench type shooting on the ground… not as long range, and at live targets instead of paper! So I guess not like F-class… More like A-class… “A” is for awesome!!! 🙄
I doubt that under 1000 cc will work for you. I say this because my air tube is 44 CF, unless I am hooked up to the 66 cf scba tank and then it is a third larger. 😛
Seriously, that will work fine. Obviously your going to be shooting from a bench most of the time s like me your air tube size does not matter that much. Tofazfou hunts jacks with his, so he needs all those shots, for me the only hunting ZI will do with mine is a few squirrels from the deck here, or I will go to my old calling grounds and I don’t need more than one or two shots per stand.
My tube I believe is 242 CC’s.
That will be a cool build Caboose,
Regards,
Roachcreek
This is the creator of the Sumo, Chip Smith… I wanted to throw this in here to show the sheer size of this action. This rifle has one Ti reservoir, and total as you see it weighs 18.5 lbs. My rifle (hopefully) will have two of the same cylinders, and a shrouded barrel… oh, I’m in for it this time!! $$$$$$ 👿 :8: Don’t care!!
The last image shows the difference between my original action idea (Gordon Dawson custom… AWESOME!!! great guy too, no homo. little longer than a standard Rapid action), and the Sumo Action, which is above it… Hopefully all my theories prove right, and the Sumo with custom internals will be able to do the job… The Sumo was originally intended for benchrest, but it’s just so much bigger, and flows a lot more air… *crossing fingers* 😈 :8:
I just had a thought- would 800+ cc be viable for shooting .257?? I have an idea to use two Ti cylinders, both a hair over 400 cc, and putting them together (like those AA S500 TC’s) to make the 800+ cc’s… it’s only around 3-400 cc more than standard tanks, and only 200 cc less than originally planned… I’m hoping it’ll be enough for around 10-13 shots before refilling. plus I can over charge the cylinders, possibly to 3100-3200 psi safely… that’ll net me some more air. Of course, Ced you’re right- tune for efficiency, but I need a solid plan before the build… gimmie a sec, I’ll post a pic of the action I’ll be using… :8:
I agree with RC.
With only the 3000-MAYBE 3200 psi fills, I would stick with 1-14 and the lighter Lyman bullets. Going up to 100 gr + bullets will really suck down some air vs the lighter 60-80 gr fodder but can be easily shot with that setup. EASILY. With 1000 cc’s of air and moderate velocities, you should get a decent shot count (20). Those Lymans will perform at 900 fps and up. So that’s a good starting number FPS wise. Forget all out FPS, tune that valve for consistency. Treat it just like a Diablo shooter and your groups will be great.
Caboose, when your gun is complete or even right now during the process, I would really love to add your pics to “OUR” 257 dedication page. I’m really happy to hear about your SUMO actioned 257. See, there I go, I done already named your gun…………..The SUMO 257.
MAAAAAAN, I’m A FRIGGEN GENIOUS 😆
Ah yes- a google search did reveal his website to me… good stuff there!! I wonder if the Mod’s could bump this over to “Other Guns”? I’m not sure if this is appropriate for Mods and Machinists… That was my fault. Thanks all for any help!! I can’t wait to show it to you guys!! After my little soiree overseas, I’ll be home to build this monster! 😈 :8:
Caboose,
That is a good little bullet. Eric at Hollowpointmolds.com will hollowpoint it for you, he did mine.
RC
it definitely helped!! Roach, your advice is always welcome! I’ll be building something out of the Sumo action by a guy named Chip Smith- he’s over on the Airgun Advice and a benchrest forum. It’s pretty much a super-built FX receiver that flows a lot more air, and is hand made. He’s built a flow through bolt like an FX Elite, or Boss, before FX built it. It was designed for unlimited benchrest. Or I’ll build off of one of Gordon Dawson’s custom actions. I’m going to have a guy over on the Airgun Advice forum, 220Swift, do a twin tank set up for me, with two 500 cc Theoben tanks. Good call on the mold, as I’ve been looking to use the lyman 257420 mold that Ced uses in his rifles. It’s inexpensive, and readily available. I think there’s someone who can modify it into a hollowpoint mold as well. So If I wanted to later experiment with those I can just buy another mold and cast FP and have the same type of bullet but in a HP. That’s much later though- I have to build the rifle first! I’m always getting ahead of myself! Thanks again! If anyone else has any input, it would be greatly appreciated!! :8:
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In order to run a line from a 4500psi bottle to the 3000psi af tank, you would need a reg on the 4500 psi tank. Otherwise, the pressure would be far too high for the af tank. And that kind of reg is quite large.
A shame we can’t get our hands on a cf bottle the proper size. Somthing on the order of the bottle being used on the Evanix Monster. Hmmm-something to think about. 😉
Knifemaker