Doing valve work in preparation for 52 grain bullets
I have RCBS 25 acp mold coming the first of the week, I also have some bullets coming from a TAG member from his RCBS mold. I have not mentioned his name, so he does not get besieged with requests for bullets if he wants to chime in he can.
He is sending me two different diamater bullets so once I find out what my rifle likes, I will order a custom sizer die from Lee Prescision.
The thought is that if the bullets don’t shoot in my gun, I will send the unused mold back.
I have been shooting a RLAirgun valve stem and Tophat turned all the way out to .0650 or so and the powerwheel maxed out.
With Kings I get 1065 FPS with a 2500 PSI fill, any more than that and it valve locks. If I load two kings in to see what the 51 grains does, I get 850 FPS.
The member sending me the bullets gets 918 FPS with a stronger spring, a AF hammer, no Condor weight and a 177 valve.
First I tried the RL stem, Airacher valve retainer and spring with a AF Tophat to get a tophat setting of .110 and the Condor hammer and weight and full powerwheel setting. Not much difference than what I had before for velocity.
Then I put in a 103 grain hammer I got from Subsonnic. I filled to 3000 PSI, velocity incresed to 1150FPS with Kings and 930FPS with two Kings. Eventually I set the tophat back to .85 and got 1162 with Kings and 945FPS with the double King 50.8 grain load. That should put those 25 ACP bullets right around 100 FPE.
Another combination I tried was the Airarcher barrel ferrel, spring, hammer, valve retainer and spring and RL valve/AF tophat set at .120 and spring and a 3200 to 3400 fill depending on which gauge I use, yes even the big gauges are eratic. I got 985 FPS with the double King load, I was still in the 1165 FPS with a King. This set up uses a lot of air for the added velocity, the shot string was very short, so I decided to go with the 945FPS/100 FPE comination to start with.
I shot some Kings at 25 yards with the 1162 FPS velocity, accuracy was about what I get at 80 yards with the 1065FPS velcocity which is around 3/4 of an inc.
It seems breaking the sound barrier with Kings makes accuracy go to hell, gosh whoduh thunk. 🙄
I will let you folks know how the 25 ACP bullets shoot when I get them the first of next week, hopefully they will fly straight enough to give me accuracy capable of shooting larger varmits.
BTW, the 25 ACP pistol round gets 750 FPS so this is a 200 FPS increase with an airgun.
Regards,
Roachcreek
All Replies
JVH,
Thanks for joining in, are you using one f the NEI designs, that one you have on order looks intersting.
NEI has moved around and changed hands a few times, when I lived up on my remote mountain, they were close neighbors to me, well 78 miles was close.
I got spoiled because I could go down and talk to the original owner, Walt, and search his mind for designs. I had a 3040 Krag 220 grain mold, a 320 44 mag mold and a 40 S&W mold that I got from him.
Welcome aboard,
Regards,
Roachcreek
Also Nei Handtools makes very good molds. I think RCBS 57902 is same like their mold.
I have this:
Just asked them to make custom mold like this:
Bullets are very accurate when selected and cast carefully. Biggest problem is to get straight cut to the bullet back. when it is ok, I can shoot 0.4-0.6″ groups to 55 yd. and 2-3″ to 164 yd. But if cut is not straight and perfect. groups can grow to 3-4″ at 55 yd.
Her is my gun
valve:
My gun can shoot those bullets up to 1017 fps. but velocity goes down every shot. 15 first shots of .25 kodiacs are supersonic.
But, This gun USES air !
20 shots from 68 cu bottle : 3045 psi –> 2320 psi
20 shots with kodiacs : 3045 psi –> 2465 psi
I have Leupys custom hybrid hammer weight 85gram, max. strength mainspring and modified hi-flow valve.
tophat setting 0.11″
The ones I got from a guy who tried to copy the specs and I only got about 2″ at 50 (worse than Eun Jins). The 62s do just under an inch.
Secoda,
My mold was delivered at the post office today.
But I am in no hurry to pick it up, reason being I want to see how the slugs I have coming shoot. If they don’t shoot at least an inch and a quarter at 50 yards, then I will not use the mold and just send it back.
Normally 1.25 at 50 yards for a air rifle would not be acceptable, my Ranger 45 will do that all day at 50 or 100 yards with cast bullets at 600 FPE, but for what I want to do with it it will work just fine at that accuracy level.
Thing to remember, at 900 FPS a Condor 25 with LDC is quieter, more accurate and has as much power as a Ruger 22 auto with a can.
Granted a little harder to carry in a shoulder holster. 😉
I have a buddy that casts but i will buy the mold. I saw all of his stuff and no thanks. I don’t even want to mess with the lead. He has everything for his pistols and powder puff loads he does all of the time plus the sizing equipment. For now I’ll machine down the Surefire 62s and see how they do. If that works well enough forget the mold.
Sounds like a great idea. We have Missouri Bullet close by but no one I know of commerically casts the .251 slugs. The ones I received were ok but not great accuracy in my Condor so I suspect some tweaking on the sizing may be necessary.
“Trouble is Lee Pricision does not make the dies in .251. They do make them on a custom basis however for $35.00 postpaid. I have bullets coming from the RCBS mold in a couple of sizes. I will slug my barrel and send the bullet to Lee Prescision for them to make a sizer. “
SECODA,
Unless your a caster already, it can get expensive.
At one time I owned 33 bullet molds, way too many. I competed in 1000 yard Black Powder cartridge shooting and cast to a wieghed + or – 1 grain on 550 grain bullets, I ended up with 40 or 45 for every hour of casting, the rest went back into the remelt. But I also cast with gang molds for my 45 and 44 and did not weigh them, just visually inspected them.
I sold everything I had but my luggage and the clothes on my back and decided to live in asia for a while, so I had to start over again from scratch.
When I got my 45 Ranger, I did so with the desire to start casting again which I did. So I have a pot and ladle and I use a little Lee portable handpress to size using their nose first sizing dies.
I have owned several of the Lyman 450 type sizers by lyman and RCBS and dislike them, they ruin a lot of bullets and are far more intrusive to the bullet than the cheap little Lee PRescision sizing dies. So I prefer to use the Lee dies and pan lube with SPG for PB’s and use Johnsons paste was for the airgun stuff.
Trouble is Lee Pricision does not make the dies in .251. They do make them on a custom basis however for $35.00 postpaid. I have bullets coming from the RCBS mold in a couple of sizes. I will slug my barrel and send the bullet to Lee Prescision for them to make a sizer.
I use that portable press on my 408-420 grain bullets, depending on the alloy, and I lube them with Johnsons paste wax before and after sizing. I like the paste wax because it dries on the bullets, but I have used Moly spray also.
It would be interesting what the velocity would be with a Sumatra levergun and these bullets.
Regards,
Roachcreek
Here is the mold. Still got to size it.
https://www.midwayusa.com/viewProduct/default.aspx?productNumber=106910
So he is using a .25 ACP mold pistol. Perfect. Those are an RCBS 2 cavity mold. 1 MOA would be impressive.
“And the .24975 and 12 bhn combo has given me the consistency that is needed . The softer lead would strip back to the base of the bullet and groups were hit and miss . The harder lead is more plastic able than the softer lead and works well for me . At this time I do not have any of the bullets that were shearing back to show you . I have remelted them to shoot again . Marvin”
These are the slugs I tested that someone tried to copy but they didn’t give me the same accuracy as Marvin is getting. I suspect there may some significant tuning involved.
http://talonairgun.com/forum/viewtopic.php?t=18094&highlight=melloroadman+2311
I am no good at doing links, so look up a post by Melloroadman dated 2-3-11 titled “casted and chroyed for my Condor”.
He is getting MOA at 100 yards.
Regards,
Roachcreek
Syn,
Seems to me that if you left that brass insert partially unscrewed, you still have to measure tophat clearance form the bottom of the tophat to the top of the brass insert.
The tophat clearance will still be the same.
I just use needle nose pliars to remove my brass insert by putting the tips of the pliars into the two recesses.
Tophat clearance is a matter of how far out the on the stem the tophat can unscrew.
I suspect I have a tired spring that is responsible for my sluggish veleocities, however shooting Kings, I can’t accurately take advantage of more vleocity they way it is.
Yes your right about the 52 grain bullets, they may be a game changer.
The wrench that R&L sells to swap out the spring and valve stem removes the brass seat that the top hat is measured from (as opposed to removing the entire valve body from the tank). A couple people here were leaving the seat proud of the valve body to restrict the movement of the tophat. If the seat is left proud it narrows the tophat gap.
Knowing that R&L sets stuff up for power at 0.088″, your 0.065 sounds a bit small and could account for the lack of velocity.
The top hat has threads but it’s the end of the valve stem and the amount it is threaded that sets the max tophat gap (on the stock AF valve that is). I’m not sure how much the R&L valve deviates from the stock conditions.
If I were to remove the threads closest to the valve seat I could increase the tophat gap on a stock Condor valve stem past the 0.162″ I measured earlier…
I have also noticed that if the tophat and stem are totally depressed so the hat contacts the brass retainer the valve will have a tendency to stick and not return and thus case a valve dump…
I’m very interested to see how these medium heavy bullets work. Could be a worthy round for decent velocity and penetration while leaving the rifle with the same setup to run a lighter pellet.
I was getting 1020fps easy with 30 grain 25 cal pellets from a stock Condor valve and hammer weight, 24″ barrel with the PW set a half way and the tophat at 0.088″… I would go as far as to call that a tuned down Condor set up from what I could get if I set the tophat gap at 0.110″ and turned the power wheel all the way up. That same valve came set from the AF factory with a 0.110″ tophat gap.
I got the very first Stubby Extreme made on May 6th. I suspect the valve has had a few tweaks since then.
I will crank out about 30 of the 50 grain slugs and give them a try this weekend hopefully. With my 18″ barrel (valve is in the Condor now) I am expecting right about 900 fps. I will be happy with anything under an inch at 50 yards. The bullets should fly with a bit more stability than the 6 – rings given the same spin.
80,
I really know nothing more than what I wrote about the 177 valve.
Regards,
Roachcreek
RC,
You mean to tell me he is getting that kind of fps with a .177 valve? I thought the .177 valves were “restricted flow”? Are they smaller than talon SS valves???
I am also curious about his spring. I have heard many gurus advise against changing the spring weights…most have left this part out of the quest for power and efficiency. Did he mention how it affected cocking smoothness? and was it a longer spring or heavier?? Thanks.
I also have tried the Airarcher power system with my 7 rings and I found that power gains where minimal compared to wasted air.
Airgunner….I would much prefer a one piece hammer (regardless of weight choice) over a two piece airforce hammer. I think most will agree that one piece means better shot to shot consistency.
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JVH,
Real nice rig. Yes how uniform the base of the bullet is – is very critical to accuracy which is why I am machining the Surefires. 1017 fps at 115 fpe is very good performance and the accuracy is great. Are you still using the std choked LW barrel? Do you know what the BC of those casts are?