90 FPE .224 Marauder
hey-Hey!!!,
I built a.224 Marauder around a TJ Hornet liner. 27″ barrel, 14″ twist and installed a 53 ci Catalina tank for the air supply. It has a custom valve, and a pull back bolt with a flat face. Firing position leaves no part of the bolt across the transfer port, though an adjustable stop to act as the velocity needle does in the OE valve is next. It shoots 20 shots across about 350 psi with a 15 fps spread centered on 950 fps. Boolits from a Lyman 43 gr mold that turns out to be 45 gr with 2% Tin content alloy. Boolits lubed with 30 wt Bel Ray fork oil. The barrel requires a weight to tune the oscillation, and with a short bit of adjustment tuning I get dime sized groups at 40 yards consistently…:) more work is required to set the weight right where it belongs. This down from a group size between an inch and a half and an inch and a quarter. Weather warm enough to shoot w/o freeing one’s fingertips would be most welcome.
cheers,
Douglas
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That’s a good question.
Might not be a problem because the slugs are not that heavy. Worst case I think the return spring would have to be stiffened up.
A little hard to do when your making the barrels by roto-hammering them with a mandrel in the center. Christianson Arms puts a carbon fiber shell on theirs and they are very accurate, but those are pb barrels in fiberglass stocks.
I doubt that you would have the problem with vibration in a Condor with the barrel bushings, PAK has his free floated which would make it prone to vibration I would think.
Doug how would the smaller bore affect your valve as far as tank dump?
I built a.224 Marauder around a TJ Hornet liner. 27″ barrel, 14″ twist
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The barrel requires a weight to tune the oscillation, and with a short bit of adjustment tuning I get dime sized groups at 40 yards consistently…:) more work is required to set the weight right where it belongs. This down from a group size between an inch and a half and an inch and a quarter.
Would a shorter barrel be more accurate due to a lower amplitude of the oscillations? I wonder if TJ’s has ever tried a cabon fiber tube bonded over the barrel liner instead of steel.
Very reasonable pricing.
Yeah sometimes a little warm is the best way to get good bullets. What are you shooting yours in and what is the mold, alloy, load and velocity?
22’s will cast fine with a fine tuned mold, just near frosting , to fill . 🙂
$4.45 a inch up to 29″, $4.75 for 30″ and up + $14.60 for shipping.
How much does TJ’s get for a barrel?
Pak,
I am really glad to see you made that work.
There is no reason that a 22 cast bullet would not shoot well in a barrel designed for it.
My hat is off to you.
I see no reason a Condor SS with the same barrel and Dougs valve would not work with a 22 and make it quieter to boot. Only draw back I can see is casting experience, meaning new casters, but after a month or two you would have the skills needed if you did your homework and those slugs would start dropping nice and crisp. You have to remember our grandfathers generation was casting for 22’s and doing some great varmit work with them.
Sweet!
Good looking stuff!
Knife
The tube/tank interface is a custom hunk o’ 7075T6. The 9098’s is just on a different CL than the Condor tanked ones. I got a small pile of the Condor tank adapter kits made and have none left for a short spell. As soon as some warm weather comes around, will be out shooting away. Awaiting a custom sprue plate for the TL225-40-RF; the one that came wid that 6-cav is just dreck…:) In the meantime, will be running the 46.5 gr Hoch nose pour…those are sweet liddle pills. The NOE ‘107’s are quite nice…and I want to try a custom sizer on them…right now I run about .2242, and I want about 2/3 of a thou smaller…
cheers,
Douglas
some bottle projects from the kit I made( each one a different project ):
http://www.gatewaytoairguns.org/GTA/index.php?topic=61527.0
http://www.gatewaytoairguns.org/GTA/index.php?topic=62950.0
http://www.gatewaytoairguns.org/GTA/index.php?topic=62862.0
http://www.network54.com/Forum/581291/message/1391306534/Benjamin+Marauder+Bottle+kit.
I’m wondering how those North American Arms bullets will perform in it, as they are intended for .22 pb barrels in .223 dia. I always wondered how a Marlin .22 pb barrell with the micro grouve rifleing would do with them. As it should have lesser friction. And they have always had outstanding accuracy! 😉
Knife
Finally! Someone in This Country tried it. I’ve been suggesting this for years. Way before the Drummen Sinner in Europe came into being. 😉 😀
Let me know how the north american bullets do as well. I may have some here still. (If I havent melted them down to cast fot the .257. LOL!!!
Looking forward to hearing how the NOEss’ shoot for you.
Lastly, what kind of header or connection did you use for the Bottle conversion”
And Just for YOU= :8: Well Done!!! :8:
I was supprised the barrel weight made that much difference. Most of us would have just assumed it didn’t shoot for crap. Good for you sticking with it!
Knife
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I’m also curious about theories regarding barrel weight placement to cancel oscillations. Any good articles about this. Where is the rule of thumb starting point for placement.? Do you just go after the low order harmonics such as 2nd or 3rd? Or use a golden ratio placement of about 39% from the end? And my other question: Wouldn’t a shorter barrel be more accurate?