Powder Idea!!!!

[Hotshot12]

While I was thinking over my reloading topic an idea struck me that I felt needed to be asked. I'm also not sure if it is any of the reloading manuals because I have not had a chance to get a hold of one yet. Anyway back to the question. Could you safely use a fast burning powder in a cartridge that normally uses a mild burning powder to substitute for barrel length so that you can still obtain the higher velocity that you get from like a 28 inch barrel in a 22inch barrel just by substituting the powder. In my mind it should work, but the factor that most concerns me is would the pressure be to much for the cartridge to handle when you use the faster burning powder? Safety is always a number 1 concern. The idea is for a .308 caliber rifle. Just wanted to know your thoughts, concerns, and if it is possible without major damage to youor the firearm.

 

[cuate]

For your own personal safety and the health and long life of your firearm it is prudent to stick with the loading manual's suggestions. A deer. hog, or two legged zombie will not notice the differing velocity of say a .30 caliber bullet from either a 22 inch barrel or 24 incher. It is suspected that the paper onthe range will not either but "kabooms" occur regulary with excessive
loads.

 

[c_m_shooter]

100 fps is not worth blowing up your gun and injuring yourself. It won't kill a deer any more dead.

 

[Hotshot12]

Alrightthanks guys it was jus t a thought and figured that something to the effect of "bang no more gun and injured shooter" would occur. Thanks again.

 

[ROGER4314]

SAAMI specs determine the pressure allowed in each load. The pressure may be designated in PSI or "copper units of pressure" and requires special equipment and relentless testing as powders change over the years. Whenever I get the big head and attempt to outsmart millions of dollars of research by jacking with a charge/load, I take my life in my hands.

I know guys who duplex (mix) powders, overcharge 110-125%, invent their own loads and do everything in their power to dance with the Grim Reaper. I wish them well but for me, if a load/charge is not printed in a manual, I won't load it. So far, I still have my fingers and body parts intact and I've been loading since the early 60's.

Charges listed in the manuals conform to SAAMI specs and that's good enough for me. If you don't know about SAAMI specs, then please research it and find out for your own safety.

Flash

 

[Texas1911]

i know a guy that loads blue dot and h110 in his 223, but he also shoots 36gr vmaxes at almost 5000fps too it all depends on your knowledge base and how to work up a load

4000 FPS would be more reasonable, I see no way of pushing a .223 Rem to 5000 FPS without blowing the case apart.

Faster burning does not always equate to better velocity. It's simply pressure over time, and in that regard, you'll never match the potential in a shorter barrel until you reach the limit where the case volume is expended and friction overcomes the energy of the pressure gradient, as is the case with long barrel .22 LR rifles.

Ultimately, most of the cases are pushed to their limit in terms of safety. There are a few case / powder combos out there that you can push well beyond book numbers and not see pressure signs, but jacking up the pressure doesn't necessarily give major gains in speed.

One thing to consider is that the burn rate will vary significantly as summer moves along. What isn't hot in the winter might be blowing the primers out during the summer.

 

[Texas1911]

There's no proof or mention of .223 pushing 5,000 FPS. Just that it theoretically could do it based on the load vs. case abilities. The most I've seen out of the .223 is a bit over 4,000 FPS which is no different than .204 Ruger or .22-250. I have yet to see someone put their face behind a 75,000 PSI rifle load, that's the over-pressure limit for proof-testing barrels on M4s, and over the pressure limit for testing .50 BMG barrels.

You'd have to be brain damaged to load something that hot.

 

[Peter M. Eick]

Just for grins.......

That means this is NOT LOAD DATA AND I AM NOT RECCOMENDING IT!!!!!!

Quickload says if you want to get a 27 grn HPBT bullet to 5000 fps you would need 20.5 grns of AA2 and you would generate a peak pressure of 253,747 psi with a 24" barrel. This is 103% loading

Your gun would go "boom" and you would cease to exist at that level of pressures. That is detonation levels. But it could be done, if you could find a strong enough chunk of steel (most I know fail at around 180,000 lbs so you are on your own).

If you are interested, 23 grns of AA5 gets you 153,504 psi
26 grns of AA9 gets you 147,823 psi and 102% capacity.
21 grns of power pistol gets you 136,997 psi and 111.4% of capacity.

Thus Power pistol is about the limit of what you can cram in.

Regardless, 5000 FPS is "unlikely" with a 223. Just not enough case capacity.

If I switch a 22-250, you can get there with 41 grns of 3031 which is 120% of capacity so pretty hard to get that much in it. This only takes 71,453 psi so marginal.
with 22-250, 4227 is a better choice. 35 grns will get you 5000 fps with only 86,102 psi and 104% capacity.

If we switch to the 220 swift ackley, then 47 grns of 3031 will get us there with 55,643 psi. This is marginal but "safe"
51 grns of 4320 will get us there with 104% capacity and 59,807 psi.

Anyway, I was just playing in quickload. None of this is real data. DO NOT USE THIS DATA FOR LOADING, IT WAS DONE FOR EDUCATION ONLY IT IS NOT REAL!

 

[robocop10mm]

You can opt for a faster powder to partially compensate for a shorter barrel, BUT it must sitll be an appropriate powder for the cartridge. Switching to Bullseye in a .223 would be flirting with major disaster. Look up "smokeless powder relative burn rate chart". Check the published data for the load and chose the powder that is the fastest on the chart. The load still has to be in the published data. Most manuals list the powder charges from fastest burning to slowest burning.

I am very skeptical of 5000 fps. IIRC there were some tests done 20+ years ago with 105mm MBT rounds. Sabot rounds in a 105 are about as overbore as you can get. The conclusion was that smokeless propellant has the potential of giving an ABSOLUTE MAXIMUM velocity of about 5000 fps if you load ridiculous amounts of powder behind a small bullet. A .22-50 BMG wild cat can do no better than 5K. Another guy used a .25-06 and .25 ACP bullets and was only able to attain about 4500 fps

 

[robin303]

Why don't you get this to get you started. Loadbooks USA "308 Winchester" Reloading Manual - MidwayUSA