My personal .450 goal....

[TacoTaco]

All,

I have a goal regarding my .450: I want to be able to *safely* work up a load to push a 300gr XTP Mag out of my 16" Bushy at a velocity comparable to mt 250gr FTX's. (~2200 fps) Ultimately, I'd love to *safely* create a load similar to Trident Armory's .450 +P (2500 fps), but I need to walk before I can run. Here's a few questions for the gurus...

1) First, are my goals safely obtainable?

2) Will the relatively low chamber pressures of the cartridge hide/mask over pressure signs??? I don't have much experience loading low pressure cartridges....

3) I worked up my first 300gr XTP Mags all the way up to Hornady's max load (32.2gr Lil Gun) with no ill effects. I now just finished loading up my next trial lot with 32.7gr Lil Gun. Is working my loads up in .5gr increments the best way to go? Too much/too little of a step up in charge weight?

4) I've had great luck with Lil Gun pushing the 250 FTXs...but is Lil Gun the best powder for the 300s??? I have some H110 and Win296 laying around....would they be a better choice?

Any help you guys can give is much appreciated. I have my first Chrony coming in from Cabelas by the end of the week and I'm eager to try it out!!

Thanks again!

[commander faschisto]

I'm sure you'll find out all you'll need to know soon...and Wildcatter will be glad to see your deliberate approach to this, like he says all the time: "Safety First!"

About all I know to tell you is that you will probably have quite a challenge getting a 300-grainer to 2200fps out of the carbine-length system of your rifle. As I understand things (if at all...) you might really need a rifle-length gas tube, and you'll have to slow down the timing of the BCG to keep it locked up as long as possible.

Let us know what you find...

[Texas Sheepdawg]

I would imagine T is gonna mention a different powder other than those already discussed. 1680 comes to mind. But I am gonna sit back and watergate this thread. I'm very interested in your results.

[TacoTaco]

I'm sure you'll find out all you'll need to know soon...and Wildcatter will be glad to see your deliberate approach to this, like he says all the time: "Safety First!"

About all I know to tell you is that you will probably have quite a challenge getting a 300-grainer to 2200fps out of the carbine-length system of your rifle. As I understand things (if at all...) you might really need a rifle-length gas tube, and you'll have to slow down the timing of the BCG to keep it locked up as long as possible.

Let us know what you find...

I'm a little ignorant in this area....but to me it makes sense that the fast burning powders used in the .450 (shotgun/pistol powders) would be better served by a shorter gas system vs rifle length. I'd assume that it's most consistent pressure curve would be closer to the point of ignition....but I could be totally off base here. The only reasoning I have is using the 5.56 setup: conventional wisdom stated that mid/rifle length gas systems run more reliable than carbine length systems. Is this due to the slower burning rifle powder? (H335/Win748/BLC2, etc etc) I don't know the answer....but hopefully someone who does can chime in and learn me a thing or two!

[Wicked Hunter]

My 2 cents.
I think if you ask James from Trident he will tell you that the 2500 fps is for the 250gr FTX but dont quote me on that. Tridents uppers are also built tougher than Bushy's. Maybe James can chime in on it? I havent seen anything from him on here for a while. I will say that with the 300gr XTP Mags i am running Win296 out of my Trident upper. They group really well. But I dont remember the fps right off hand. I'm thinking it was around 2100.

[Hoot]

According to QuickLoad, which tracks pretty close using 1680 and the Barnes 275gr, in the case of AA1680, you're going to be maxed out on powder capacity with the 300 XTP Mag loaded to 2.26 COL about the time you arrive at 2200fps in a 16" barrel and you will be blowing ~6% of that powder out the barrel unburned. Pressure is predicted to be 50% beyond SAAMI recommended max at that point. That's all I'll say about that part. What you choose to do WRT the SAAMI recommendation is up to you. FWIW, the 20" barrel only gains 100fps and ~4.5% unburned powder ejected. I hope to do some more runs of both W296 and 1680 with the Barnes this weekend, so I'll have more data in that thread.

Hoot

[Texas Sheepdawg]

Whoa. I need to step back and rethink this. Thanx for the heads up Hoot.

[wildcatter]

OK, here goes..

Forgive me, if I sound dubious and standoffish.

You have entered an area that if I give an affirmative answer, "You" might be OK, in your work, but someone with way less experience might have a barrel rupture. Even though, we use disclaimers, the fact will be that I/we could be judged as encouraging "Dangerous Loading Practices".

So, here's the partial answer.

Your project is possible, but a barrel rupture is even more probable, and its accompanying injuries to your body. Trying to get to a specific FPS, is in fact a recipe for disaster and in a 16" barrel, making this project even more dubious and dangerous. It is better to load up slowly and let the pressures rule the final FPS, and, you will hit the "Wall" as I describe it, well before you hit your target speed. The Wall being, when the rifle starts to short stroke, because of timing issues associated with your load/gas port location. And you will need a rifle length gas solution to increase the "Wall" Timing. Trident loads, I imagine, are right at that Wall, and could, on a hot day, start short stroking. Though not dangerous, can be problematic, assuming some animal is trying to stomp a Mud-Hole through you. I also assume, his loads have been tested, under Hot conditions and are safe to use. I do this in a temperature-controlled oven, set at 150 degrees, If I don't have pressures problems, from that heat, I'm going to have to look to other areas of concern, for my pressure problems, dirty chamber, case lengths, etc, etc, etc. I'm trying to impress the reader that there are a thousand things that can cause pressure problems and they all seem to Coalesce, at the same time and at the point when things are going to get real dangerous.

Now, again, forgive me for being Negative, for your goals are possible, but even if you do get to them today, you're so close to the edge, that even tomorrows weather could cause you serious troubles.

So then, try if you must, we didn't make it to the moon without killing some fine people, but protect yourself, be ready to absorb the cost of killing your rifle and don't blame anyone, besides yourself, if you get hurt. For I do such things, but I have the scientific equipment to help me along and I have made the statement, that I have blown-up more rifles, then most men will own.

Hoot sometimes thinks I hold my cards too close to my chest and would like me to reveal more than I do and he's right. I fear the Tort and what it's become. Now, in private conversations with someone as experienced as our Hoot, I can talk freely, but then that person already knows their limitations.

In other words, to be "Official", your goals are too high, with the experience you have. So, don't do it..

..t

[Texas Sheepdawg]

Thanx Tim!

[bigboreshooter]

All,

I have a goal regarding my .450: I want to be able to *safely* work up a load to push a 300gr XTP Mag out of my 16" Bushy at a velocity comparable to mt 250gr FTX's. (~2200 fps) Ultimately, I'd love to *safely* create a load similar to Trident Armory's .450 +P (2500 fps), but I need to walk before I can run. Here's a few questions for the gurus...

1) First, are my goals safely obtainable?

2) Will the relatively low chamber pressures of the cartridge hide/mask over pressure signs??? I don't have much experience loading low pressure cartridges....

3) I worked up my first 300gr XTP Mags all the way up to Hornady's max load (32.2gr Lil Gun) with no ill effects. I now just finished loading up my next trial lot with 32.7gr Lil Gun. Is working my loads up in .5gr increments the best way to go? Too much/too little of a step up in charge weight?

4) I've had great luck with Lil Gun pushing the 250 FTXs...but is Lil Gun the best powder for the 300s??? I have some H110 and Win296 laying around....would they be a better choice?

Any help you guys can give is much appreciated. I have my first Chrony coming in from Cabelas by the end of the week and I'm eager to try it out!!

Thanks again!

I have some 300 gr Speer deep curls that I will be shooting soon out of me 16". I'll let you know the fps and post some pics when I do.