Minimum bullet size

[Yooper003]

You might try ordering raw boolits at .432 then powder coating them. Not too much of a job & should bring them up to .434

[cmat1120]

You don't say what you are using the rifle for but if you scale back the velocity the softer bullet will expand to the barrel size and your accuracy will go up.

Plinking mostly, but eventually hunting as well if I ever pull a unit with thick brush. I want an fps range around 1200-1500 for hunting(whatever I can max out at using unique powder), but besides that I don't care. I was under the assumption higher velocity = more obturation and therefore the bullet will fit the barrel better. Isn't that why high BHN bullets require magnum+ velocity? A lot of people with the same rifle report good accuracy and a clean barrel with low BHN bullets(10-15) once they find a bullet that fits the barrel correctly.

[cmat1120]

Just got back from the range today and the jacketed bullets shot very accurately so I'm pretty confident the other bullets I tested were either too small or too hard or both. I've pretty much given up on finding commercial over sized bullets at a reasonable price so I might get into casting myself after all.

[DougGuy]

throat size, not groove size!!!!!!!

^^^^ this.

Just got back from the range today and the jacketed bullets shot very accurately so I'm pretty confident the other bullets I tested were either too small or too hard or both. I've pretty much given up on finding commercial over sized bullets at a reasonable price so I might get into casting myself after all.

J words for all the hate they gather here (LOL) are wonderfully adept at obturating to fit the throat, and the groove, they are a dead soft lead core swaged into a fairly weak, thin, very malleable gilding metal jacket. You can fire j words through a severe thread choke, and with sufficient gas pressure behind them they will swage down to go thorough the choke, then bump back up to fill the bore. Pretty cool how they do that if you ask me.

Soft alloys will do the same in your rifle, if you load .432" over full house loads of slow burning powder, they will fill the throat and seal pretty well by the time they exit the case mouth. Too small boolit diameter, and too hard an alloy, will always be problematic. Does this make any sense?

[waksupi]

Throat size, not groove size!!!!!!!

I tried to explain this to a very experienced shooter this past weekend, and he thought I was nuts. Kind of hard to argue with him, as he is a real accuracy nut, and whatever he does seems to work well.

[cmat1120]

^^^^ this.



J words for all the hate they gather here (LOL) are wonderfully adept at obturating to fit the throat, and the groove, they are a dead soft lead core swaged into a fairly weak, thin, very malleable gilding metal jacket. You can fire j words through a severe thread choke, and with sufficient gas pressure behind them they will swage down to go thorough the choke, then bump back up to fill the bore. Pretty cool how they do that if you ask me.

Soft alloys will do the same in your rifle, if you load .432" over full house loads of slow burning powder, they will fill the throat and seal pretty well by the time they exit the case mouth. Too small boolit diameter, and too hard an alloy, will always be problematic. Does this make any sense?

Yep this makes complete sense to me. From what I understand the only reason to find a size that "fits" is so you can use harder bullets to avoid gas cutting. I've heard mixed things on the next part, but since I'm using a rifle even my moderate loads using max pressure of unique powder are going to be going fast enough that a soft bullet will lead regardless of how well it fits. That seems to be the only reason I would need to look for these bigger diameter bullets. All I want is bullets that are accurate and don't overly lead my barrel. From my research I see no terminal ballistic reasoning for using lead any harder than 8 bhn. Commercial lead is all much much harder though so without proper fitment I know I'll have all kinds of issues.

I wish I could cast myself as I would really like to be able to find that sweet spot of using a more "standard" 432 bullet and experimenting to see if there was a bhn where it obturated well and also didn't lead. That kind of process is why I am interested in getting into casting.

As for the throat size comments I do get that its the most surefire way to get proper fit. If you put a bullet in that's as big as will chamber, chances are it will be well over bore size. I'm pretty sure that's why matching throat size works so well. I definitely get why you guys are recommending it as its simply fool proof. If I could I would be following that recommendation. The reason I started this thread was because I have not yet gotten into casting so I was hoping I could find info on a minimum size in the hopes that it would equate to something I could buy commercially. If I was able to cast myself I'd get a mold made to drop 0.434+ bullets and call it a day.

Fortunately I'm going to get to try some bigger cast bullets from a member here and see how they do. I'm guessing their performance will convince me to start casting my own as soon as I can.

[yeahbub]

A softer alloy around 8-10 BHN will allow some boolit upset to improve sealing in the grooves, but they can't be drivien hard or they'll leak. YMMV. A card wad and lube cookie will help with that. The next step up is a gas check design. Matching alloy hardness to desired velocity and pressure is a big part of success.

It's good you've slugged the barrel. Did you happen to notice whether there were loose or tight spots? Or a reverse taper, tight at the breech and loose at the muzzle? Tight spots or reverse taper will produce indifferent accuracy with cast with just about any boolit/load combination, but jacketed may do better. It's fairly easy to correct with pressure-lapping as the difference is usually less than .001. It's more prevalent in round barrels that have been bored/reamed/rifled and then lathe turned to outside contour, allowing unresolved stresses to cause the barrel to "spring", more where it is thinnest. Not all barrels exhibit this, but it's not uncommon.

Powder coat could give you that extra bit of diameter to bring a boolit up .001 or so. Maybe someone can send you a coated handful to try.

Another possibility is to paper patch a few and size them to the diameter you need, keeping in mind that paper will spring back .001 over what the size die is, so a .432 sizer will produce a .433 boolit. Paper patching doesn't require much investment; a ruler, disposable razor knife, some Elmer's glue and some ordinary notebook paper will do. One doesn't do this to turn out thousands of them, but for experimental proof-of-concept purposes or making enough for hunting, they can provide another avenue of approach. One nice thing about PP is that there's no lead to steel contact at all, so your barrel stays clean of any lead fouling and soft lead can be driven hard with a paper jacket. There's a sticky on this site you can mine for info to see whether you'd like to give it a try.

[cmat1120]

A softer alloy around 8-10 BHN will allow some boolit upset to improve sealing in the grooves, but they can't be drivien hard or they'll leak. YMMV. A card wad and lube cookie will help with that. The next step up is a gas check design. Matching alloy hardness to desired velocity and pressure is a big part of success.

It's good you've slugged the barrel. Did you happen to notice whether there were loose or tight spots? Or a reverse taper, tight at the breech and loose at the muzzle? Tight spots or reverse taper will produce indifferent accuracy with cast with just about any boolit/load combination, but jacketed may do better. It's fairly easy to correct with pressure-lapping as the difference is usually less than .001. It's more prevalent in round barrels that have been bored/reamed/rifled and then lathe turned to outside contour, allowing unresolved stresses to cause the barrel to "spring", more where it is thinnest. Not all barrels exhibit this, but it's not uncommon.

Powder coat could give you that extra bit of diameter to bring a boolit up .001 or so. Maybe someone can send you a coated handful to try.

Another possibility is to paper patch a few and size them to the diameter you need, keeping in mind that paper will spring back .001 over what the size die is, so a .432 sizer will produce a .433 boolit. Paper patching doesn't require much investment; a ruler, disposable razor knife, some Elmer's glue and some ordinary notebook paper will do. One doesn't do this to turn out thousands of them, but for experimental proof-of-concept purposes or making enough for hunting, they can provide another avenue of approach. One nice thing about PP is that there's no lead to steel contact at all, so your barrel stays clean of any lead fouling and soft lead can be driven hard with a paper jacket. There's a sticky on this site you can mine for info to see whether you'd like to give it a try.

I didn't notice any tight spots, but I was also using a pretty crude method(too soft of a wooden dowel and a big *** hammer lol.I didnt push the bullet all the way through the muzzle either, just into the rifling about 6 inches and back out(also squished it a bit in the middle from both sides to get better groove fill out). I also have an octagonal barrel so it sounds like that might be less of an issue. Either way I'm guessing it'll wear out any tight spots after 1000 jacketed rounds anyways. If this next test with bullets from a member here doesn't give me adequate results I might look into the paper patching to vary diameter more. From what I've been told on this thread and by PM it sounds like some larger softer bullets should work a lot better than what I've tried so far though.

I appreciate the suggestions a ton!

[WRideout]

One alternative that hasn't been mentioned is trading for boolits that someone else has cast. I've gotten quite a few different types and calibers of boolits from people on this site, and have provided boolits that I have cast as well. Usually people will take brass, tools etc. for boolits. I don't usually see home cast boolits for sale, but if you put up a request in the appropriate sub-forum someone may just give you a sample of what you want. FWIW.

I just realized I didn't read a previous post completely.

Wayne

[cmat1120]

One alternative that hasn't been mentioned is trading for boolits that someone else has cast. I've gotten quite a few different types and calibers of boolits from people on this site, and have provided boolits that I have cast as well. Usually people will take brass, tools etc. for boolits. I don't usually see home cast boolits for sale, but if you put up a request in the appropriate sub-forum someone may just give you a sample of what you want. FWIW.

I just realized I didn't read a previous post completely.

Wayne

That was my plan once I had enough posts to be allowed to make a WTT or WTB post. As a new member you're not allowed to do that though. Fortunately a moderator on here saw my thread and private messaged me and I just got the bullets today. Very excited to give them a test hopefully next week.