Loose bore = Less Velocity?

[crashlanding]

Greetings,

I have a rifle that is a wildcat. I am not getting the velocities without pressure that others have seemed to get listed on here. Not even close.
I am curious if a "loose" bore would cause the lack of velocity? Meaning, I am using more powder to get the same velocities, but the bore is so loose that it just doesn't get it moving??? I have had a tight bore on a Christensen barrel that pressured fast, usually around start loads.

When I push a patch through, it is kind of loose compared to my other 338 barrel.

Anyone else have this before?

Your description fits a rifle and cartridge I bought earlier this year, I am happy to hear I'm not alone. Hopefully with the new brass I bought, this may or may not be rectified, otherwise back it goes. On a bright note, I did manage to load something that prints one ragged hole at 100 yards but velocity is still lack luster. I need this rifle for this hunting season so I'm going with it

 

[44-40]

Slugging the bore will give you the smallest dia of the bore, if pushed through...but you can feel loose spots, the slug moves easily. Lapping the bore you can feel loose spots, gas ports, tight spots, and concentrate on evening it out a bit.

 

[lancetkenyon]

Let's have the specifics instead of being vague.

Hard to give suggestions on powder and velocity without knowing anything beside .338, 213HH, and Varget. Could be a .338-308AI to a .338 ENABLR.

 

[Elk Hunter 338]

You should also be skeptical of what other wildcat shooters are getting with their rifles. If there was ever a bunch of guys who liked to push the outer limits of practical pressure, they reside in the wildcat crowd. No offense intended to anyone.

 

[Shane Lindsey]

Was actually trying to leave that out, but it's a 338 Sherman. Using Peterson 280AI brass.

 

[Elk Hunter 338]

what velocity are you getting with it!! ????

Barrel make ??

Etc.??

 

[Shane Lindsey]

213 Hammer Hunter 2677 FPS with Varget.
175 Hammer 3065 FPS with CFE 223.
These are the only ones that shoot at least MOA. Both line up with Hodgdon's 338-06 data, towards the top. My velocity is a little slower due to 22" barrel length, but thought I would be gaining a little with the increase in case capacity.

Everything else I only did one round per charge weight for velocity/pressure. All were low before I got ejector print where I wouldn't go further. Backed off and just no accuracy, so moved on to another bullet.

These are where I had pressure, no accuracy.
250gr Hornady BTHP 2617 FPS with Staball 6.5 and 2601 FPS with H4350 (I don't think they make this anymore).
200gr Nosler BT 2867 FPS with Staball 6.5 (no longer made).
225gr Speer BTSP 2701 FPS Rl17.
250 Bergers was able to get to 60.3gr Rl17, but never clocked it as accuracy wasn't there so moved onto the ones above.

 

[lancetkenyon]

So nearly 2700 with a 213 from an 06' based wildcat. Sounds pretty impressive to me. I am running a .300PRC AW2 and running a 215 Hyb @ 2860fps. I got up to 3055, but give me accuracy over raw speed any day. Plus, it is a lightweight running suppressed, so I will take less recoil as an added bonus.

I take Sherman data with a grain of salt...and I have a BUNCH of Shermans. And a lot of the info on their spreadsheet was supplied by me. I have tested a couple of the first ever chambers. But I do my own testing. And I think I am pretty good at reading pressure signs and have very realistic expectations of where velocities should be. I would be researching .338-06AI recipes.

I don't always go with the conventional powders. There are more commonly used powders like BL-C2, Varget, H4350, RL17, but I wouldn't discount RL23, N560, maybe even N565.

 

[Shane Lindsey]

Accuracy isn't great. I did look at 338-06AI data as well, just didn't find as much.

I guess I bought into the 2800 FPS with a 250 Berger. I have some Rl23, but thought I would run out of case capacity.

 

[Elk Hunter 338]

Accuracy isn't great. I did look at 338-06AI data as well, just didn't find as much.

I guess I bought into the 2800 FPS with a 250 Berger. I have some Rl23, but thought I would run out of case capacity.

2800 with a 250 anything is in 338 win case cap of 85gr -- 340 weatherby case cap of 90gr territory vs what? 75gr case cap in an "IMPROVED" '06 case?? sorry you would have to beat brakes of that sucker to get that
@lancetkenyon said it best 2700 in a '06 sized case W/213 gr bullet is no slouch

 

[Shane Lindsey]

It will work for here. So it sounds like the barrel is probably ok, just expectations and or advertisement got me...

Got a 22" CF 338 Lapua barrel and a can on order for further out.

And as soon as they move me to the fry station...that's when the big bucks start coming in.

 

[Phil Rizzo]

It will work for here. So it sounds like the barrel is probably ok, just expectations and or advertisement got me...

Got a 22" CF 338 Lapua barrel and a can on order for further out.

And as soon as they move me to the fry station...that's when the big bucks start coming in.

If all the "aces" would just tell the TRUTH about velocity and accuracy it wouldn't plant false seeds of hope. Fat Chance!
ultimately our own data counts the most. And we learn who to believe eventually. And who to snicker at!
Hope you end up pleased.

 

[Calvin45]

Oh good grief yes now that we know roughly what capacity of wildcat we're talking this seems like perfectly reasonable Performance.

Just as a reference, my .358 Norma magnum drives a 250 hornady interlock to 2900 fps IN A 27.75 INCH BARREL!

An 06 capacity case doing what yours does out of a 22 inch sounds right to me.

 

[Barehandlineman11]

Just run it at 165,000 psi itll be alright