AJC1
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Obviously undersized bullets cause a bunch of issues from terrible accuracy to leading. What is the upper limit and what do those indicators look like.
Accuracy implications of oversized cast bullets
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The Glockodile
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Not sure.
The .356 125 grain HAPs are quite accurate through typical 9mm barrels, which typically take .355 bullets.
With cast lead bullets not having a jacket, I imagine they'd obturate the bore better - but as to what extent this'd be beneficial, not really sure.
The .356 125 grain HAPs are quite accurate through typical 9mm barrels, which typically take .355 bullets.
With cast lead bullets not having a jacket, I imagine they'd obturate the bore better - but as to what extent this'd be beneficial, not really sure.
earplug
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Upper limit of being undersized? I don't understand the question.
Much depends on the ability of the bullet to seal inside the bore. Powder type, pressure and bullet size and hardness all effect the outcome.
I have found that as big a diameter bullet that will chamber is a good place to be.
Much depends on the ability of the bullet to seal inside the bore. Powder type, pressure and bullet size and hardness all effect the outcome.
I have found that as big a diameter bullet that will chamber is a good place to be.
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AJC1
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As the title says upper limit of oversized. Undersized is well known and discussed ad nauseum
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AJC1
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Rifle is the primary quandary but if there are differences I'd like to know. I'm inclined to believe that limits are close to deformation limits used in swaging them to size but that is a mental exercise I'm playing with zero testing or evidence.
Charlie98
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I would think a too large of bullet for a bore would result in pressure spikes... even if it swaged down into the bore, I wouldn't be surprised with an over pressure spike.
It depends on where it is too large. Generally if you get too big, you will run into chambering problems. With my bullets and loads I'm usually not pushing the pressure limits of the cartridge so I've never ran into pressure spikes that I have noticed. I shoot .453 lead bullets in most my 1911's, .311 bullets in .300 blackout, .357 in 9mm, .358 or .359 in .38 Special etc. Generally all are my own homecast lead bullets. Sometimes a bullet can cause the brass to expand just enough to cause chambering problems but usually it's the front driving band that starts to hit the rifling that causes an issue. Bullets size easily enough that once the gunpowder kicks then in the rear they will shrink to whatever the bore and groove diameter are very quickly.
With certain rifle bullets you can run into problems with the bullet nose being too large and not chambering.
With certain rifle bullets you can run into problems with the bullet nose being too large and not chambering.
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AJC1
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.311 in a 308 is giving me fits but I think they may be better in 30-30 due to a looser bore. I'm honestly not exactly sure what the problem is or if there are multiple issues. Different Bullets sized .310 were better and shot near moa. Lee sells .309 and .311 sizes so I may try traditional lube and size 310 at my dad's place.
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AJC1
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Those were out of stock for the last 2 years I've been looking to get them...
Bearded Phil
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40 some odd in stock now. Just need to grab this and whatever size bushings you want. It says "die body" but it's everything you need less the sizing bushings.
https://noebulletmolds.com/site/sho...ough-size-die/001-push-through-size-die-body/
Use code FLT001 for 10% off.
I got one of these during the 4th of July mould sale when I was getting some moulds. Haven't picked up any bushings yet, I'm going to wait til after I can do the cerrosafe cast on my barrels which I... still havent' gotten around to, haha.
Edit: You'll also need a push rod or Lyman style top punch depending on which way you want to size. As I understand, the NOE sizing system will seat and crimp GCs if you size them bottom up with a top punch.
Basic pushrod (nose first) for 30 cal
https://noebulletmolds.com/site/sho.../bushings/30cal-bushings/30cal-push-rod-30pr/
Hooda Thunkit
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I use the NOE system to seat and crimp gas checks.
Nose first through the die; the standard pushrod holds the check in position.
Works like a champ.
As for the upper limit of oversize - that depends.
I shoot 358 in all my 9mm pistols. From a Star 30M to an Astra M70 to a SCCY to a S&W Shield. Even more than that, but you get the idea.
358 in all my 38/357 revolvers.
For rifle, well... If you go too big you will run into the diameter of the chamber. I have, and had to turn necks.
Other than that, shoot however large you need to make it work.
Generally, 2 or 3 thousandths will work.
GeoDudeFlorida
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Like I posted in the thread about .314” bullets, I buy .313” cast, gas-checked, Hi-Tek coated bullets for my Mosin-Nagant M38, M91/30, and SMLE rifles with bores ranging from .311”-.315”. The only similar rifle they don’t work in is a Finn M39 with a .310” groove and .304” bore. They don’t group well, do seem a bit spikey and it seems like they deform at the base so the gas-check ends up kinda wrinkled looking. I suspect there’s just no place for the extra material to go but back, over the check and that makes it spin off center some. I can typically hold a 8” pie plate with a SMLE or Mosin and with good .311” cast 180’s that M39 will do much better. Not with the oversized bullets though.
Not sure if that helps. You know what they say about anecdotal evidence.
Thank you for the heads up on the sizing push through die. I too have been looking for one for months. Just ordered one.
Bearded Phil
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I'll have to give that go when I get there. Thanks for the heads up!
.308 Norma
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It's been a while, but I had a couple of Ruger .45 Colt revolvers that had slightly undersized cylinder throats. So, when I shot cast bullets that were .001" over my barrel (groove to groove) diameter, the bullets got swagged down before they entered the barrel anyway.
I've always been a bit OCD when it comes to handloading, so I had those cylinder throats reamed out a bit. I can't remember the details, but I do remember that having the cylinder throats reamed a little didn't improve my shooting much, if any.
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Barbaroja
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At least you couldn’t blame the cylinders after thatIt's been a while, but I had a couple of Ruger .45 Colt revolvers that had slightly undersized cylinder throats. So, when I shot cast bullets that were .001" over my barrel (groove to groove) diameter, the bullets got swagged down before they entered the barrel anyway.
I've always been a bit OCD when it comes to handloading, so I had those cylinder throats reamed out a bit. I can't remember the details, but I do remember that having the cylinder throats reamed a little didn't improve my shooting much, if any.
IIRC; I read some Schutzen shooters used breech loading bullets up to .008"-.010" larger than groove diameter. For all of my cast bullet sizing I mostly limit bullet diameter to chamber size (some bullets are sized so the cartridge will just fit the chamber, rifle calibers). Lead bullet vs barrel dimensions is a largely discussed subject and more than bullet diameter comes into play and accuracy was not overly discussed in relation to bullet diameter vs barrel dimensions. I remember an experiment where a .17 caliber barrel was chambered for 22 lr. No pressure problems and exciting velocities and good accuracy resulted...
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AJC1
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Bearded Phil
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It would be interesting to see the effects of accuracy on a known good load at .001"-.002" over bore diameter that was increased to .003"-.004".
Would take some meticulous testing though. And I think the consensus here is "will it still chamber" is an obstacle. Also, it might require someone to permanently lap their mould a bit to be able to drop a bullet big enough.
Would take some meticulous testing though. And I think the consensus here is "will it still chamber" is an obstacle. Also, it might require someone to permanently lap their mould a bit to be able to drop a bullet big enough.
Charlie98
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I tried to get .350" cast bullets from Montana Bullet Works, for my .348WCF... they said no can do... .349" was as big as they could go, because that was the biggest mould regularly available.
You will recall that in my Savage 99 lever-actions... my .30-30 must have a .310" bullet or they shoot shotgun patterns, I've often wondered about going to a .311" bullet, just to see what happens. As it is, my .308 99 shoots .309" bullets just fine, but also shoots .310's as well, too... so nothing lost there. It would be interesting to see what would happen in both rifles if I went to .311"...
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NuJudge
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For rifle, you need to size cast bullets for the throat, which is probably going to be at least .002" larger than the groove diameter. On bolt actions, having the bullet pushed into the rifling on loading creates no problem with slam fires, and supports the bullet on firing such that it does not slump to the side, which always gives poor accuracy. Some of the old NRA publications have excellent pictures of this. With semi-auto pistol, I like the bullet to be groove diameter, but in some pistols a cartridge assembled with that fat a bullet will not chamber in some pistols. For revolvers, I like Lead bullets to be throat diameter.
Bearded Phil
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