How much is too much?

[Harter66]

Having spent gobs of time roaming around in here ,I've not seen an answer that was clear to me.

Rule of thumb is .002 over maximum bore and a little more for a loose throat.
If it chambers freely shoot it.

Well I've a 7.62x39 SKS that slugs just in front of the throat at .3145 and .314 at the now back bored muzzle . The last 1/4" was belled to .320+ . The thing is I had some C-324-175 2R out of pure for sluging so for gee-wiz I belled a fired case and ran 1 through my .323 push through sizer and it would go in the case just a little tighter than slip fit, not really slip but nowhere near press fit. So the next step is to close the bolt ,not only does it close but it does so with half of the top lube groove out of the case and just contact marks not cuts but heavy land dimples on the radius of the nose.

Well w/o thinking any further I loaded some with 8.0 Unique and shot a lovely little 6" 50yard group of 10 a foot right and a foot low. I've had worse 1st loads. Having only emptied the factories for the brass and knowing it holds a foot or so with .312 js in this rifle I really have no expectations of moa groups. Derailed I've fired 30 rounds in the gun period. A little lead at the muzzle,but there's still some copper too. The rifle looked like it had a case of ammo through it and stored in a draft when I got it.

So how big is too big ?

[leftiye]

Get a chamber cast. Slug the bore just in frunt of the chamber. Without these, neither you nor I can answer your question. Sounds like you have a muy loose freebore area. It is often said that one should fill the freebore in such cases.

[geargnasher]

Yes. Fill the freebore with steel from a new barrel.

As far as how big is too big, it depends. I have no rules. I have one rifle that shoots best with hard boolits sized to exactly groove diameter and can be pushed to nearly 2700 fps with decent accuracy. I have one revolver that can shoot up to .005" oversized boolits. If you're worried about excessive pressures from going too big, I'd say the only thing to worry about is whether or not the case neck has room enough to expand in the chamber neck so the boolit will release. It doesn't take much room for that, less than .001" clearance is plenty.

Gear

[btroj]

What you say Gear? No rules? Everyone knows that without rules in loading and shooting cast we are lost.

I believe that Gear is entirely right. Every gun is a rule unto itself. Find what a gun likes and all is good, give it something it doesn't like and you get leading. The key is finding what it likes. No rules to this. It is the experimenting required to find this that separates the men from the boys in cast shooting.

Brad

[geargnasher]

*sigh.....* I knew someone was going to blast me for saying that!

Gear

[warf73]

I'd say the only thing to worry about is whether or not the case neck has room enough to expand in the chamber neck so the boolit will release.

This is the rule I go buy and hasn't lead me astray yet, not saying its the best way to go but it works for me.

Warf

[noylj]

I hear people worry about over-pressure from using bullets that are "too" large.
It seems to me that as handloaders, whenever we change something (and we should only change one thing at a time), we drop back to the lowest starting load various manuals refer to or the starting load for the next heaviest bullet.
My 0.3555" 9mm CZ-75 barrels are quite happy with 0.358-0.359" bullets.
As long as the loaded round drops in the barrel with a nice "clunk."

[1Shirt]

If it fits and it works, don't fix it! Go as big as needed, and when needed is adequate stay there!
1Shirt! :coffee:

My mosins and 303' like as fat as I can cast and as long as they chamber and shoot accurately that's all I care about!

[Bret4207]

Do I understand correctly that this 7.62 rifle will easily chamber a cartridge with .323 boolits? Holy short case neck life Batman!!!

Hey, if it works and you're happy, fine, but I'd be looking for a barrel/rifle with decent dimensions if it were me.

[MtGun44]

Remember military rifles, esp Rooskie military rifles put going 'bang' WAY ahead of
hitting the berm in the correct half.

Bill

[btroj]

*sigh.....* I knew someone was going to blast me for saying that!

Gear

Sorry about the flogging, hope you heal quickly.

[Jack Stanley]

Gear , don't let 'em kid ya . You HAVE rules ......... just go count the firearms you have and you can tell 'em how many rules books you go by :mrgreen:

Jack

[Harter66]

If it'll fit in the spent case and chamber freely trigger it. Ok. Being a mechanic at my core I can make it visualy workable and see why its "not not okay". Thanks gear.

Yes it will chamber a .323 band and base that is a friction fit in a fired case. No flat primers and no attempt to cycle this tired lil Yugo.

I bought it from a fellow down on his luck and as is my custom "its mine but I got a deal so anytime for a year you can buy it back for what I paid." . 322 days to go then I can bbl it or bore it or what have you.

[runfiverun]

i'm just trying to picture the squeeze and how the lube is taking that.
anyways it sounds like a good learning opportunity....

[btroj]

Gear , don't let 'em kid ya . You HAVE rules ......... just go count the firearms you have and you can tell 'em how many rules books you go by :mrgreen:

Jack
That , my friend, is almost the truth. He needs to count guns AND how many loads he has for each. Each load/gun combo has it's own rules.

And yes folks, that is ALOT of rules. And most have nothing to do with each other, but they all work.

[Harter66]

Well,I moved to my stash of plain base boolits . Shot 5 each at 8,8.5,9 gr of Unique with Darr's lube a little heavy on STP . The bore stayed clean but streaked a little and I think would benefit from being LLA'd before sizing.

Intrestingly the 8gr load strung verticaly about 2x4", the 8.5 was horizontal about the same,the 9gr was roundish at 2.5". More to come .....

[chboats]

Harter66 - I have a 7.65 Argentine Mauser that the throat and bore are so washed out that I shoot a 323470 sized at .325. I had to thin the necks of the brass to .010/.011 so that the round would chamber. If I do my part it will shoot 2 - 2 1/2 inches at 100yds.

If you tried a smaller boolit it would probably not shoot as will as it does and lead more.

[Harter66]

I've too much time on my hands.
I could go a whole new direction,I could patch up to bore dia with a couple of my 30s. Maybe not whole new bucket of snakes semi auto rifle might not be the best place to learn.