How much throat erosion is “normal”

[Mike Matteson]

Bullets don't erode throats. Have shot out several barrels and 2 things have always been the deciding factor:
Number one is powder type, powder temp and chamber design.
Number two is how fast you shoot.
It is proven that ball powders, although double base, have a colder burn and the flame front moves through the powder faster before the powder column starts being moved past the throat. This protects the throat both from the heat, but also the abrasive nature of the powder.
Extruded powders, regardless of composition, are abrasive, single base burns hotter than double base, but double base has more energy and scrubs the rifling harder. In this scenario it is the abrasive nature that erodes the rifling, not the heat.
I had 2 identical 30" barrels in 300WM I used for mid range F-class. One was fed H1000 only, the other was fed RL25 only. Accuracy fell off the RL25 barrel first after 1400 rounds and a total of .089" throat erosion, a set back had it in new rifling and the accuracy returned. The H1000 barrel lasted 1680 rounds, had .079" throat erosion, but the rifling was smeared for another .100" from I assume was the plug of powder being forced down the barrel. A set back of 2 turns was needed to get into fresh rifling.
So, my take on this is that double base extruded powder is actually nicer on barrels, if I had of set back at .080" erosion, it would have been better in the long run. I get 3 set backs on these barrels.
I was not sponsored, so I had to pay for my barrel blanks, here in Australia a barrel costs over $1000, so not cheap at all.
A reamer only costs a few hundred and is affordable. For my 300WM I use the A191 chamber, you can look this up.

Cheers.

Interesting. I do have a question. I though that people down under weren't allow to have firearms anymore? I tried to follow what's going on around the world. The person that walked and shot a bunch of people several years ago. Got your semiauto and pumps removed. Now I not going do anything, but this is what I felt. That person that shot those people could have done it with a single shot rifle.
My real question is why the people allow the government to take there firearms away? Can't all be leftwinger down there.

 

[VinceMule]

Mike, I pretty much ignore cratering of primers in large rifle primers. My 257 Weatherbys crater primers tremendously. The firing pin hole in the Remington bolt needs to be bushed. I know a great guy to do this kind of thing in San Diego, who has done most of my bolts that I shoot small rifle primers in, 223 AI, 6 BR, 6 Dasher, 6 XC, etc.

 

[Aussie Hunter Steve]

Interesting. I do have a question. I though that people down under weren't allow to have firearms anymore? I tried to follow what's going on around the world. The person that walked and shot a bunch of people several years ago. Got your semiauto and pumps removed. Now I not going do anything, but this is what I felt. That person that shot those people could have done it with a single shot rifle.
My real question is why the people allow the government to take there firearms away? Can't all be leftwinger down there.

We can still own firearms here but the conditions imposed are getting more onerous as the left chips away.... different states have differing restrictions, and some are banning various cartridges, especially the long range capable rounds, although we've never seen a long range mass shooting! Currently there's a push by government to implement a national forearms register- it just goes on and on....
Waterfowl hunting is under siege, as is bow hunting although the various groups and clubs are pushing back against it. The majority of our voting population are confined in a rather small urban environment and don't understand the vast rural landscape we have. Unfortunately the wrong done by a few bad guys impacts upon the whole shooting community as authorities impose their knee jerk reactions.

 

[Frank in the Laurels]

Frank, my 6 Dashers have around 1100 rounds of usable "best" barrel life and at 1400 rounds, the barrels are completely shot out. H4895 burns very, very hot.

Varget varget varget....it all depends on what type of accuracy your talking about..ours are used in benchrest leve VBRl at 850-1000...

 

[Rflshootr]

These temps are taken in calorimeter bomb tests, the same tests used to determine burn rate by INDIVIDUAL COMPANIES. There is no standard that these tests are put beside, so there is no way to know exactly if this temp is the same in a rifle barrel because cartridge size, design and other factors make it virtually impossible to use this info in your barrel or cartridge. It also doesn't state how much powder is used to get the result.
Peeing into the wind at least has a result you can relate to.

Cheers.

Wouldn't peeing in the wind have different results depending on the pressure your weapon has and the wind speed?

 

[MagnumManiac]

Interesting. I do have a question. I though that people down under weren't allow to have firearms anymore? I tried to follow what's going on around the world. The person that walked and shot a bunch of people several years ago. Got your semiauto and pumps removed. Now I not going do anything, but this is what I felt. That person that shot those people could have done it with a single shot rifle.
My real question is why the people allow the government to take there firearms away? Can't all be leftwinger down there.

Well, yes and no. Our stupid legislation here has a follow on effect since 1996. I married crazy and when I left her last February she made claims of family violence…falsely made accusations. Had all my firearms confiscated, thrown in a cell for several hours and proceeded to get a 10 year ban from holding a firearm license and my livelihood.
She knew what I would lose, had the kids make false statements and made sure I lost the lot. No longer can work on firearms, possess or use them due to stupid laws here. I did none of the things she accused me of.

Cheers.

 

[Mike Matteson]

We can still own firearms here but the conditions imposed are getting more onerous as the left chips away.... different states have differing restrictions, and some are banning various cartridges, especially the long range capable rounds, although we've never seen a long range mass shooting! Currently there's a push by government to implement a national forearms register- it just goes on and on....
Waterfowl hunting is under siege, as is bow hunting although the various groups and clubs are pushing back against it. The majority of our voting population are confined in a rather small urban environment and don't understand the vast rural landscape we have. Unfortunately the wrong done by a few bad guys impacts upon the whole shooting community as authorities impose their knee jerk reactions.

I figured as much. Just like here. They get dumber by the second! Mexico-North (aka Calif) band 50 cal rifles a few years back. I guess they felt that a 37+# rifle, people were just going to run around and set up and shoot everybody. Plus they cost over $5,000.00+ at the time. It's sure not the run of the mill firearm.
I don't think anybody is going to run to far with that weight.

 

[Calvin45]

I figured as much. Just like here. They get dumber by the second! Mexico-North (aka Calif) band 50 cal rifles a few years back. I guess they felt that a 37+# rifle, people were just going to run around and set up and shoot everybody. Plus they cost over $5,000.00+ at the time. It's sure not the run of the mill firearm.
I don't think anybody is going to run to far with that weight.

I've mentioned this in two other threads but your post reminded me yet again…up here in Canada the .460 weatherby and rifles chambered for it are now arbitrarily banned among many other "big guns" - too powerful.

But my pistol gripped 14 inch barrelled 12 guage pump that I can fit in a backpack is just fine, don't even need a restricted licence for it, no ATF up here or need for a tax stamp or ffl…i ordered it online completely legally with my standard license and it was delivered to my mail via Canada post no questions asked.

I think it'd be funny to present those brilliant feds with a graph or chart comparing the number of crimes committed with sawed of shotguns vs weatherby safari rifles


But then they'll ban shotguns so maybe not…

 

[Mike Matteson]

Well, yes and no. Our stupid legislation here has a follow on effect since 1996. I married crazy and when I left her last February she made claims of family violence…falsely made accusations. Had all my firearms confiscated, thrown in a cell for several hours and proceeded to get a 10 year ban from holding a firearm license and my livelihood.
She knew what I would lose, had the kids make false statements and made sure I lost the lot. No longer can work on firearms, possess or use them due to stupid laws here. I did none of the things she accused me of.

Cheers.

I've see that here in the US. My brother X tried almost the same thing. The courts found the hole in her statement. Told her if anymore faults statement were made she would go to jail. He's been married 4 time. Doesn't learn. About got all his money and half his pension too.
Mexico-North is about as bad. (aka Calif) and few other state are dumber than rocks. In Montana and several other states you can carry just about anywhere. I really feel that cuts into people wanting to be bad boys. They don't know who they might be backing into. That's a good thing. From what I can see the courts are the same ways, dumber than rocks too.
Been a member of the NRA from almost the time I ETS from the Army in 1970. Life member of the Cal Rifle & Pistol As. My borther and I fund both org. everyyear.
Those people on the left side of things need a specail place for them. and live in the big cities. Not allowed out. Can't move into a state that allow people to carry firearms. That way we would all be happy.
I know that most of the kids I when to school with done hunt.