Downloading for barrel life?

[Keyst0ne]

As I understand it heat (driven by velocity x bearing surface) is the major factor in killing a barrel. Case geometry is a contributing factor as well.

So can a chambering with a "barrel burner" reputation achieve a usable life similar to a lower power cartridge with a loading that more closely approximates that lower cartridge?

For example I believe a 300wm generally has a barrel life of 1,500 rounds or so under a competition firing schedule (i.e. 10 fast rounds, then cool). 308win typically gets twice or better life.

If I were to lightly load a 300wm such that it was pushing a .308 bullet (perhaps heavier than typical 308 loads) at closer to .308 speeds, would I see something closer to 308 barrel life, but have the ability to step it up for matches or higher power needs?

 

[AIAW]

You could, but generally you’d need to speed to achieve stability on the heavier and longer bullets. The lighter bullets are likely to have a ton of jump (not necessarily an issue). The problem is that a lower case fill is also going to render generally more erratic velocities. Not always the case, but how the powder column is laying the case is a variable none the less.

Plinking would be fine, but if you are expecting utmost accuracy loading then that way it isn’t going to be reliable.

It is possible that a particular powder would solve this in order to get a decent case fill. I am out of town this weekend so I have no access to QuickLoad in order to sort of do a comparison on pressure/velocity.

I can’t recall my load data when I was shooting barrier and 168’s out of a 300WM.

H4831SC perhaps?

 

[Supersubes]

I think simply finding your low node and shooting that would do what you need. Pushing for the last 100-150 FPS is what’s doing the throat damage in many cartridges imo.

Here’s an example. People are smoking 6 creed barrels in 1000-1500 rounds. This seems crazy to me, but I believe them. Im running a low node experiment on a barrel I chambered earlier this year. 115’s at 2880 in a 27” barrel, and stupid accurate. Most are running 2975-3050. I’m 400 rds in and the throat hasn’t moved a single thousandth. Throat looks great through the borescope as well. Most are reporting 20-40 thou erosion by this time. I’ll be shocked if this thing doesn’t go 2500-3000 rds.

Regarding stability, if you have it with some margin now, you’ll probably be fine. Stability only very slightly increases with speed. There is a point I think where low charges(low pressure) stop burning well, or your cases aren’t sealing the chamber, etc.

 

[MtnCreek]

300wm will be harder on a barrel than 308 shooting the same bullet at the same velocity. More powder will be needed in the wm to achieve the same velocity.

 

[Steel head]

You can shoot the low node but trying to make 300wm shoot and last like 308 is kinda silly.
You could stuff it with really slow powder but big powder charge still eats barrels and is a waste or use light charge with lots of unused case volume which causes a few other problems.

I shoot low a lot in my 260 at shorter distances as accuracy is extra and pushing a bullet hard for under 1000 yard stuff is silly as well.

 

[XLR308]

Another option would be to choose a powder that is a little on the slow side of the optimum burn rate and cooler burning if possible.
That would give you optimum fill ratio with a lower muzzle velocity and may help prolong barrel life but like @MtnCreek allready said given the difference in capacity between the 300wm and 308win the barrel life will never be the same.
I have a load for my 65CM using H1000 and the 147eldm that just hammers and has an accuracy node as wide as barn door but the velocity isn't as impressive as using H4350 but is more than enough for target and hunting purposes and should prolong barrel life.

 

[918v]

I have my 300WM shooting like a 30-30 with a case full of Trailboss.

 

[Keyst0ne]

You can shoot the low node but trying to make 300wm shoot and last like 308 is kinda silly.

The 300wm 308 was just an easy example because they are two common rounds with known life.

I'm looking more at whether I might want to set my daughter up with a 6 creed and have her shoot light loads for practice to save barrel life and step it up for matches, but nobody is bragging on how slow they can make a 6 creed go so data is hard to come by.

 

[Keyst0ne]

In regards to stability I'm a Litz disciple and tend toward fast twists regardless.

 

[Danattherock]

I've done this but not quite to the extreme, a 6 creedmoor running 108 ELDs at 2990 and now a Dasher running 105 hybrids at 2910. The barrel life I'm assuming will be better but the main benefit for me is better recoil management and ability to spot my shots. with that said I wouldn't load anything down so far that you negate the reason to even have that chambering. But going for a lower node makes a lot of sense for many reasons in my opinion. Some of the best PRS shooters in the country are not running super hot loads, so that might be something to consider.

 

[b6graham]

The 300wm 308 was just an easy example because they are two common rounds with known life.

I'm looking more at whether I might want to set my daughter up with a 6 creed and have her shoot light loads for practice to save barrel life and step it up for matches, but nobody is bragging on how slow they can make a 6 creed go so data is hard to come by.

Do a BR/Dasher and just run the same load all the time

Or do a 223 trainer

 

[Keyst0ne]

Do a BR/Dasher and just run the same load all the time

Or do a 223 trainer

That's what I've got underway -- a 223 bolt face and one 223rem barrel and one 223ai. She can play in tactical division with the 223rem until she wants something with a little more reach (and more expensive ammo!)

 

[MtnCreek]

The 300wm 308 was just an easy example because they are two common rounds with known life.

I'm looking more at whether I might want to set my daughter up with a 6 creed and have her shoot light loads for practice to save barrel life and step it up for matches, but nobody is bragging on how slow they can make a 6 creed go so data is hard to come by.

H4895 is what you want. I did the same with a 6.5 creed and 120 amax for my kids.

 

[918v]

I think Supersubes gave the best suggestion. Run a lower node where you still maintain decent load density and your barrel and your brass will last longer.

 

[lash]

I posted many times before that I’m getting well over 3000 accurate rounds from my .260 barrels by using a lower node. The 136 scenar Ls I use can easily be pushed over 2900 FPS using H4350. I’m at a comfortable wide node at 2750-2770 and getting more rounds than most out of a barrel without sacrificing much at all in the 1000+ yards range.

You do have to be careful how long you push them though. I had one barrel crap out on me at over 4400 rounds in the middle of a 2-day match. Smith didn’t have my new barrel ready in time and I unwisely decided to go for it. Current barrel has over 3500 on it and I verified speed and consistency just the other day. Still shooting well.

 

[Supersubes]

I posted many times before that I’m getting well over 3000 accurate rounds from my .260 barrels by using a lower node. The 136 scenar Ls I use can easily be pushed over 2900 FPS using H4350. I’m at a comfortable wide node at 2750-2770 and getting more rounds than most out of a barrel without sacrificing much at all in the 1000+ yards range.

You do have to be careful how long you push them though. I had one barrel crap out on me at over 4400 rounds in the middle of a 2-day match. Smith didn’t have my new barrel ready in time and I unwisely decided to go for it. Current barrel has over 3500 on it and I verified speed and consistency just the other day. Still shooting well.

My experience with .260 is identical. I sold my first .260 with exactly 4400 rounds on it, and it was still shooting. Steady diet of 139 scenars at 2750.

A creed would do the same if loaded in the same realm I believe.

 

[Steel head]

The 300wm 308 was just an easy example because they are two common rounds with known life.

I'm looking more at whether I might want to set my daughter up with a 6 creed and have her shoot light loads for practice to save barrel life and step it up for matches, but nobody is bragging on how slow they can make a 6 creed go so data is hard to come by.

Subes did and those numbers are legit

No matter what 6 creed is a barrel burner but on the low node performance will be excellent and it won’t be a barrel torch.
Hell,,,look up ballistics if the low node, I wouldn’t even bother pushing it hard at all.