I'd like to start a conversation on how to shoot High Velocity castboolits in a stock rifle.
I believe there are some who'd like to talk about this.
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I'd like to start a conversation on how to shoot High Velocity castboolits in a stock rifle.
I believe there are some who'd like to talk about this.
Please define "High Velocity" so all are on the same sheet of music.
I also assume you are stating normal 'stock' equipment and expecting jacketed (for caliber) fps plus MOA (100yrd) accuracy?
High as feasibly possible.
Obviously higher than the typical (1600fps to 1900fps) published loads and up to the physical limits. Honestly I'm not smart enough to set the number, which I suspect will vary with caliber and other factors. This is more of a discussion of how to get there, not a actual number or range of numbers.
I'm just a pistol caster myself, but I look forward to learning how for when that time comes to cast for the o'l smoke poles.
Subscribed.
Standard rifles such as your hunting rifle, including varmint rifle, AR's, and milsurp. Some because of extreme fast rifling twists are more difficult to load for and all have an alloy and pressure limitation.
Myself I'm looking definitely above 2000 fps. Those that load in the 1600 to 1800 fps bracket can get more velocity. Besides the alloy/presure limitations, some calibers have a velocity limitation that their cartridges aren't able to achieve even with j-words. That's not to say that can get higher velocity with lighter bullets then loaded by the factory standard. I'm sure many of you know that as the calibers out there that you can use pistol/revolver bullets or bullet weights in. An example would be shooting 38/357mag bullets in a 35 Rem.
Being semi new to rifle casting except a little for black powder, I'm going to just sit by the side and watch this thread.
Well I don't know if this counts but here goes .
7x6.8 mildcat
Carcano action
Montana Rifleman bbl 21" 1-8 twist
As with all things some things worked better than others. I did get to 2375 fps with a 142 gr 27-135 papered up to .285 with quarter dia groups . 10x ,H322 and 4198 all deliver useful groups and 2300-2350 . Only really significant as this is jacketed speeds for 130s.I really don't feel like I did any especially particular with this other than attention the as cast bullets .
Next up a 6.8 SPCII AR .
Same powders . With assorted jacketed factory loads the rifle delivered 2-2.5 inch best groups at 24-2600 fp with 115-120 gr loads with 120SST I readily got 2" groups without a lengthy work up with multiple powders .
For cast I used the NOE 279-124 FP weighing in at 129 gr from 75/25 WW - 1-20 and water dropped . These are also the 1st loads I had assembled with gas checks . The bullets were culled 1st by obvious defect then by full fill out . Using 4198 allowed me to reach 2150 with nominal accuracy for the rifle . Several issues have made themselves known the chamber neck is a minimum length so the nominal case lengths were in fact too long and caused release issues in the top loads . This also lead to some fouling caused by lube failure caused by undersizing at the case mouth . Because of the muzzle device being shouldered away from the muzzle I had crown fouling that also messed with the groups . I now have a clean muzzle, recut muzzle device and a 280 sizer for the gas checks over the original 278 which worked with the 270 x 277 bbl except for the case mouth abuse. It should be noted that the 6.8 Remington is rated for 62 kpsi and 2300 fps with jacketed 130 gr projectiles so even if I am unsuccessful in breaching 2300 fps ,I need 2200, I will be well into jacket speeds.
Attention to fill out and seating plus custom expanders and partial sizing of the cases contribute to accuracy. The SPCII chamber, or at least mine , is full in the shoulder resulting in a slight increase in capacity . I believe that with the uniform trimmed length will help with the lube loss and the sizeless checking won't hurt anything.
I guess just about any fool can run 222 and 223 well over 2500 with 50-70 gr bullets so I don't have anything to add to that .
I do intend to try a 6.5 mag and 257 Roberts looking for 3100 and 2700 in each with the same bullet a NOE 260-120 fp . Of course 2500 in either or both would be sufficient.
My successes in 30 cal have been limited. Getting the accuracy and and velocity curves to match up just hasn't happened yet. I can drive hard in lead free bbls or have little groups fast twist or slow there's just no bliss. It is possible that I've not given sufficient attention to the details .
Fastest I have personally shot was a Ruger #1 in .375 H&H with a 300 gr. GC mold made by BRP. I would have to look up the alloy, but given the time frame, most likely heat treated WW at best. The gun wears a 2.5X Leupold HEAVY Duplex scope. Several groups in a row were in the 5/8" wide by 2.5" high range. Obvious vertical stringing in every group. Me? The often reported #1 stringing? The load? I dunno. Velocity was in the 2,650 fps range.
Breech seating tools, bump dies, optical comparators? Any tooling restrictions?
Breech seating? No.
Bump dies, why not?
I can give it a go with Dad's post 64 Mod 70 in 30-06.
I may see what I can get from the 375 H&H too. I have had it over 1800 with accuracy easily. Never gone faster with good results but have learned much since then.
My interest is a "shoot whatcha got" discussion. Dies and moulds are easily purchased or modified by most. Alloy, lube, and powder are the big topics I'm interested in.
If your shoulder can bear some more testing set up a chronograph and look at your ES and SD. You may be having a lot of velocity variation. If you do your powder isn't burning just right yet. Could also be caused by inconsistent crimp if you're using one and also varying neck tension.
Sounds like a good candidate for 50/50 alloy water quenched.
I agree with Btoj, lets keep it simple. Breech seating is a whole other ball game. It's specialized. Franklore is pretty good at it.
If allowed here or if affordable to whomever is doing the testing first thing would be a truly custom made mold for your rifle with as perfect bullet fit as possible since fit is king. Then on to bump dies etc. if necessary. Alloy isn't quite as important I don't think as long as fit is right. Powder choices I would say should be on the slower side that let you reach your velocity. Using "factory" molds things become a bit more difficult but not impossible. There are classes for both factory and milsurp rifles in competition and some of those guys are doing pretty respectable work.
To be honest, I'm not sure. Maybe some theory of boolit deformation ...When, where and how much is too much.
This is a discussion, not a competition. These are all interesting tools to discuss, as in, why are they used, what benefit do they offer. Also what can be done without these tools, that can nearly mimic their advantages.
breech seating tool..... I had to look that one up.
I'm going to throw out a statement for debate, just to see where everyone is in the HV game.
"Nose-bumping a bullet for HV shooting is a complete and utter waste of time".
Agree? Disagree? Why? (There's no substitute for experience here, so no WAGs please).
Gear