How fast?

[stealthshooter]

Hey fellas.

I was wondering how fast you can push a gas check bullet before you run into issues?

[John Boy]

Let's have a starting point - Your Rifle:
* Caliber
* Bullet weight
* Your velocity to fit your definition of fast

[Bret4207]

Better define "issues" too. IME it can be anywhere from about 1,000 fps on up. With perfect fit in a cast friendly gun with the right load...we have guys shooting over 2500 fps regularly and at least one shooting in the 33-3500fps range. BUT, not every gun will do that. Each is a law unto itself.

[Wayne Smith]

Also, do you include paper patched boolits in your definition or only lube groove boolits?

[stealthshooter]

My rifle is a 450 bushmaster .452 cal bullet. I have no plans of using a paper patch bullet so lube groove only. Right now I'm pushing a 300 grain bullet at around 2200fps and a 200 grain bullet at 2700+fps. I'm really wanting to shoot some cast bullets. In fact I'm melting some wheel weights and lead shot right now in preparation.

[stealthshooter]

Any thoughts?

[MtGun44]

Once you get past around 1800 or so, things start to get more difficult. Mostly keeping the
accuracy. We have had one member here shooting at 3100 fps with good accuracy at
100yds. Not easy. A bit like advanced aerobatics. Anybody can take off and land, some of
the better pilots can do loops and rolls. The very best do airshows, and even then, some of
them crash.

Pushing past 1800-1900 is like starting to do the challenging stuff. Depending on the gun, the
boolit design and about 23 other things, you may find it immediately difficult, or maybe not
too bad. Your 2200 won't be too tough, but 2700 isn't for the beginners. Most here are
more expert than I on this topic, but that is the general drift. NO hard rules.

Bill

[geargnasher]

Agreed, NO hard rules. It is up to you to figure out what your gun will do, and how to develop the load to overcome little obstacles that will arise as you try different things with your ultimate goal in mind.

Load data for cast boolits in this cartridge seems a little scarce, perhaps that's why you're here? Not many other folks shooting cast boolits in the .450? Maybe you can change that, but not knowing your level of experience shooting cast boolits, it's hard to give much advice. If you are brand-new to the hobby, you have a way to go before jumping in with both feet on this one.

I really have no tips other than the conventional places to begin: "Slug" your barrel with a soft lead slug to get an accurate groove dimension, make a chamber cast or "impact slug" of the chamber, throat, and rifling origins, determine magazine maximum OAL, select a boolit of the correct weight that has a nose profile and size that fits the throat and contacts the rifling upon chambering (hopefully while lining a crimp groove up with the case mouth at your preferred trim length, size the boolit to .001" over groove diameter, use a good lube, select a powder suitable for the pressure range, velocity, boolit weight, and expansion ratio of your case, work up your loads carefully, and make adjustments as you go.

Gear

[303Guy]

It seems that slower powders can deliver higher velocity with lower pressure with fewer issues. Less flame cutting, less boolit base upset etc. That's my impression anyway.

[Bret4207]

If I can make a suggestion, it sounds like you're brand new to cast. There's a fairly steep learning curve to this. I'd start low and slow and work my way up. Record everything you do, never change more than one thing at a time. Unless the gods of cast smile on you I'd say it'll take a couple, 3 months at least for you to get past 2K successfully, and that's if you even like casting. Some people hate it.

[cbrick]

and that's if you even like casting. Some people hate it.

http://www.lasc.us/Holycripe.jpg

WOW, now there's a foreign concept, never heard of such a thing. Is that even possible?

Rick

[Jim]

http://www.lasc.us/Holycripe.jpg

WOW, now there's a foreign concept, never heard of such a thing. Is that even possible?

Rick

Thanks, Rick! That brought a much needed smile!:mrgreen:

[Larry Gibson]

There are some hard rules, but as mentioned, the rifle will define those rules. What is the barrel twist?

Larry Gibson

BTW; if you don't have Lyman's Cast Bullet Handbook, preferably the 3rd edition, you should consider getting it. Lot's of information for the beginner to study. Yes there are lot's of things advanced casters do that are not in there but the Handbook gives you the basics to move forward with.

[stealthshooter]

I am new to casting but I have an uncle that is going to help me and he's been doing it longer than I've been alive so it should help with my learning curve a bit. My gun has a 20" barrel with a 1 in 24 twist.

[Larry Gibson]

I am new to casting but I have an uncle that is going to help me and he's been doing it longer than I've been alive so it should help with my learning curve a bit. My gun has a 20" barrel with a 1 in 24 twist.

With that barrel you should be easily able to push a 300 gr RCBS 45-300-FN (the GC'd one) to the same 2200 fps as with J bullets. With the same accuracy also. With the proper alloy, proper sizing, good load and a good lube like Javelina there should be no "issues".

Larry Gibson

[1Shirt]

Many good words of wisdom from very experianced cast shooters. Suggest you periodicaly go back and review this thread as you learn and progress. I can offer no better than has already been provided. I like for general target and practice to stay between 1500-1800 as that is cheaper on powder and easier on the shoulder. Good luck!
1Shirt!:coffeecom

[Wayne Smith]

Consider Larry's list of conditions. It is quite succinct and correct. 1. Proper alloy - books have been written about this. Not a simple subject, but the principles are easily understood. 2. proper sizing - usually .002 more than your groove diameter. 3. Good load - if you are an experienced reloader you know the complications in that one! 4. Good lube - again, books written. Then realize that all of these work together and interact. Change one and you affect them all.

In short, the concept of spending months getting there, along with probably a couple of sore sholders, is very true!

[stealthshooter]

Thanks guys!

So you suggest .002 over bore size but what if the mold throws smaller bullets? Also what's the best way to find the bore dimensions for my gun? I know what Bushmaster claims it is but...............

[1Shirt]

If the mold throws smaller, go with Beagleing! It works!
1Shirt!:coffee:

[Wayne Smith]

Soft lead slug and a micrometer are your tools for finding the size of your bore. Do a search on slugging a barrel and you will get a bunch of information.