Hard "slugs" and pellets

I hear a lot of people in the air gun world make statements about shooting harder slugs wearing barrels out rapidy. I even see comments about pellets having a bit of antimony worry about wearing barrels. I have a decent collection of century old powder Burning single shot rifles from before the turn of the century to about 1920 that have countless thousands of rounds with harder bullets and the guns still retain gilt edge accuracy. The only wear you often see on these is from the powder heat in the throat forward of the end of the case. The metalurgy of these barrels is not what we have today I would think they would be on par with modern air gun barrels, but that's just a guess.

Has anybody done a real test and measurement to see if the statements about barrel wear in air rifles and harder bullets are true?
I had a .50 Texan and I put about 3000 rounds of linotype bullets(22bhn) down the tube And I could not see any sign wear with my gunsmiths Hawkeye bore scope,nor an accuracy fall off.

im not trying to start an argument, just looking for data .
 
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I’ve never had a concern about different hardness of lead alloys. If a modern barrel can’t handle that then I’m going with a different brand. Also the lack of heat and pressures of a PB could be in play here too.

The one thing I’ve seen where I may have some concern is these copper coated pellets. Copper may still be softer than steel but it’s gotta create more potential wear.

I’m no metallurgy guy so I could be wrong.
 
Not so much wear as build up of the copper wash which is used to prevent oxidation of the lead. Hard vs soft. rifling twist rate and depth comes into play as well as velocity. years back had a very costly 32 cal match pistol, vel. range around 700 fps - could not hit squat with it using hard cast or swagged hard lead wad cutters. switched to softer offering - pure magic. Nothing else was changed. Diameters and weight the same also.
 
It's nonsense. There are different hardness measurements but I will quote Rockwell because it's easier for me to remember. Lead is 5, copper is 10 and steel is 60. On a copper coated pellet the lead is what contacts the rifling, it is so thin the copper plating gets cut through by the rifling. My Prod prefers copper plated FTTs and I've recovered them and the lead is clearly showing at the rifling. PBs "wear out" a barrel due to the powder burning in the chamber of the barrel. We don't have that with airguns. No high heat to damage the barrel. So they will outlast us. Doesn't matter how much we shoot them or what we shoot through them. Did you ever weigh a pellet after shooting it? They don't loose weight. So even though they are soft lead doesn't wear off going down the barrel. If the lead doesn't wear, how is the much harder steel going to wear? In an absolute sense there is wear but as a practical matter it is so small it cannot be measured. It is nothing to worry about. Shoot what your guns prefer.
 
I could see the potential for lead buildup causing a drop in accuracy, but not loosing steel.
In powder, burning rifles, leading is *usually* caused by an undersized bullet( Hot gas is getting around the side) or the improper(too hot) powder charge and occasionally overspinning the projectile.
 
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I've been hearing about this since I was in diapers. The problem is people treat the subject as a nebulous topic, never thinking to apply their minds to what really matters.

If you want to get to the heart of it, read/watch here:




We are in the light load category: BHN 6-12.

Now applying this knowledge, buy this:


Then measure the hardness of Javelin, H&N, NSA, ZAN. Olympia, Griffen, AVS, and Apollo, Has anyone ever done this? I will since I'm in the business now. No more fingernail test that tells us nothing.
 
Data is always of interest but the only reason I know of to test the hardness of lead is to make sure it can "hold the rifling" when a bullet is pushed fast from a PB. We are in a totally different pressure range with our airguns so I don't think we need harder lead. But it would be interesting to see if the normal input that H&N and Crosman pellets are harder than JSB is factual or what the hardness of various brands of slugs is.
 
Measure the hardness of Javelin, H&N, NSA, ZAN. Olympia, Griffen, AVS, and Apollo, Has anyone ever done this? I will since I'm in the business now. No more fingernail test that tells us nothing.


Sonny,

I'm with you. Let's get some data — to root out Old Wifes' Tales and Senile Airgunners' Stories. 😆

Seriously, I hope you will do the testing. Here in the projectile subforum would be a great place to easily find it.
Thank you! 👍🏼

Matthias
 
with the velocity ranges of our air powered units at present particularly the larger bore units leading of the barrel likely would never happen, unless the internal quality of the barrel was that poor ( it happens). We have no or imperceptible gas cutting going on which is the bane of pb units. If you want to really get in to cast bullets there is a forum dedicated to such. Cast bullet association. An extreme case of leading eons ago - 303 enfield cast bullets, they were too soft for velocity and left a long string of lead in the groves of the exremely well used barrel pushed out with a patch all 24 + inches worth. As I stated earlier you can go too hard for a particular rig as well giving erratic performance. Twist rate, cal. , velocity, & lead hardness all have to come together to hit the magic mark. Yep, it's another slippery slope . Been casting or swagging pills for more than 30 years- still learning. I am not senile either, just been in the sports for very long time. ( just a note- lead is added to some steels to aid in machining same acts as a lubricant.)
 
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Data is always of interest but the only reason I know of to test the hardness of lead is to make sure it can "hold the rifling" when a bullet is pushed fast from a PB. We are in a totally different pressure range with our airguns so I don't think we need harder lead. But it would be interesting to see if the normal input that H&N and Crosman pellets are harder than JSB is factual or what the hardness of various brands of slugs is.
Would it be the hardness or the actual composition of the slug that determines it staying in tact vs fragmenting when hitting the target?
I tested KO's this summer and they mushroomed as well as maintaining almost all of their original weight. I recently tested some Hybrids and they seemed to mushroom but it was hard to tell as they mostly fragmented into tiny little fragments.
The fragmenting is great for squirrels and rabbits but have my doubts it would successfully penetrate a racoon skull consistently enough for me to use them.
 
I don;;t think the tendency of some slugs (and also pellets) to fragment is due to the alloy of lead used. I think it is the design of the projectile. I see the fragmentation as "over expansion". As you note, it might not be too much for some applications but it also might be for others. In powder burners there are projectiles that expand a lot without breaking up too much but I don't see that in airgun projectiles. For powder burners it is copper based projectiles that seem to be best at substantial expansion without loss of mass. The Nosler partition is another way to do it. But with a lead projectile I think we have to accept that if they expand a lot on smaller animals they may not penetrate enough for larger animals. I just use simple domed pellets. Put in the right place they work great.
 
Well I can't offer any definitive proof that hard slugs wear out airgun barrels. My opinion is that even the harder slugs are much softer than steel.

As for "hard" slugs, I've had some interesting experiences with the .20/18.9 NSA slugs on critters in the last 6 months. Over the summer I ice-picked many a prairie dog with them, often seeing the slug through and through them, even at distances past 150 yards. Full pass through evidenced by seeing the slug skipping through the dirt out past the dog.

Couple months ago I shot a Euro dove broadside through the thick wing joints and full through the breast. He was at 125 yards and the pellet still "ting"ed off the steel pipe fence about 30 yards past him. Sure didn't seem like much expansion for it to have made it all the way through the dove.

And just in the last few days I shot a house starling at 20 yards, steep downward angle. I saw the dirt splash past the hosp. Retrieved the critter and he looked like it just scared him to death, no readily apparent damage, but he was DEAD. So can't imagine much expansion there either.

I've shot over 2000 of these NSA slugs through the barrel, highest slug count I've had from a barrel. Mostly b/c they're one of very few accurate enough to shoot much. But haven't seen any signs of barrel wear and I'm not expecting it or worrying about it. Plan to shoot many more of these slugs.
 
My concern with slug hardness is not barrel wear but accuracy and expansion.
I bought a used evol with the intent of having an accurate slug shooter. However after trying several different weights of nsa slugs I gave up and went back to pellets. However recently I obtained some zan slugs and tried those, and they shot great. I’ve noticed that the zan slugs chamber much easier than the nsa’s and I’m guessing that has something to do with hardness as Nielson uses the high speed equipment that requires harder lead.
also I bought an air force Texan and several of the older nsa slugs came with it. I tested the expansion of these by shooting through several water jugs and expansion was excellent. However when I bought newer slugs (high speed press) I couldn’t get them to expand well at all.
I think the softer lead allows the slug to conform to the rifling better under the low pressures used in Airguns (compared to PB’s) and results in better accuracy and expansion.
 
your last line is true. pb units rely partially on the fast exspansion of the gas to upset the base of the projectile there by sealing the bore off, as well as driving it into the rifling. So for air units need slugs to fit very close to the major dia of the bore aka grooves vs the minor dia. of the lands. too small and they just slip by basically rattling down the bore if they are soft enough and too large then you get a smearing action upsetting the balance of the projectile and in worst case leading of the bore ( not generally an issue at our velocities). The lead pills have to be hard enough to grab the riflling without shearing?smearing but soft enough to allow the lands to engrave without shearing material away.