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rsterne · Moderator

I'm just going to let the cat out of the bag a bit here.... SeanP and I have decided that since JSB are making pellets for the FX and Daystate .30 cals that are smaller than will properly fit in a "standard" .308" barrel (LW, TJ's or PB).... we are ordering a mandrel from Mike at TJ's to have airgun barrels produced to properly fit the new 46-50 gr. JSB pellets, which have a 0.300" head diameter.... Once the mandrel is made, we will be getting some barrels done in 0.50" OD which would fit an MRod, and I will be doing a prototype riser breech to adapt that size barrel to a 22XX/Disco using a modified MRod .25 cal clip (Lloyd's) that will allow 7 shots in .30 cal.... This breech will also accept a .25 cal MRod barrel, or a .25 Auto TJ's barrel blank as well.... We already know that the .25 MRod clip will accept the 53 gr. cast Lyman bullets and the 50 gr. Mr. Hollowpoint bullets, so if all works out as planned, both the MRod and 22XX/Disco platforms will move up to shooting 46-53 gr. pellets/bullets in both .25 and .30 cal....

SeanP is hoping to produce the breeches & bolts, along with providing machined .30 cal barrels, and valves opened up to provide the additional airflow required.... I'll be doing the prototype work, and at the moment FPE numbers are just a guess, as we want to make everything as much of a "drop-in"/"bolt-on" as we can.... However, my goal is 850+ fps with the 46 gr. JSBs which would be 74+ FPE and hopefully more depending on the pressure and barrel length used.... There is no reason that shorter .25/.30 cal barrels could not be fitted to the 2240/50 pistols as well, using the new repeater breech.... Down the road, SeanP may get some 0.59" OD (15mm) blanks made and machine them up for a single-shot conversion for the QB 78/79 rifles as well.... along with matching bolts....

Please don't bug us, as it will be a while before any of this gets prototyped, let alone into possible production.... The above information is all I can supply at the present time.... My prototype will be a new project, which is a .30 cal Disco Double (from Lloyd at AirGunLab) in a Blaster stock with an MRod trigger (from Norm at DiscosRUs).... When I have anything concrete to report, it will be in a thread I will start on that project....

Bob

whm1974 · Veteran Member

Good luck to you then.

rsterne · Moderator

Update on these barrels.... The mandrel is made, and the barrels will be produced to the following specs:

.30 cal Airgun barrel intended for the new JSB 46 & 50 gr. pellets
Made from CrMoly steel, hammer forged
Groove 0.300"
Land 0.294"
Twist 1 turn in 26"
6 Lands
OD 0.500" (0.590" also available)
Standard length 25" (12.5" for pistols)

What they are NOT: They are not intended to use 0.308" cast bullets, nor are they intended to use any bullet over 0.48" in length, as those will not fit into a modified .25 cal MRod magazine, and may not stabilize in the 26" twist....

Sean will be placing an initial order as soon as we can collect pre-orders and determine a price.... For THIS ORDER ONLY, and only for BARREL BLANKS with no machining, we will accept orders for lengths other than the above, but be advised there may be a small surcharge from the manufacturer for barrels over 29" long....

I will be contacting those who have expressed an interest in pre-ordering barrel blanks.... Anyone else who wants to get in on this initial order, either for blanks or for machined barrels.... please contact me ASAP.... Sean will be finalizing the list within a week, getting prices, and then contacting you to arrange payment.... Sean will be offering all machining services (chambering, porting, and crowning, and can even add a choke) at extra cost if you desire, please ask him for details directly....

Bob

rsterne · Moderator

First results of a target, shot with JSB pellets at 921 fps average (filled for each group to 2650 psi) from the new barrels.... Not my work, a chap from Alberta, using a 29" barrel on a modded Condor at 12X....

The grid and the orange circles are 1", targets shot every 5 m from 50 m to 90 m (which is 100 yards).... I think you can safely say we did our homework on bore size and twist rate....

Bob