.264 LBC BHW barrel high pressure signs

[MTNmyMAG]

Ok any time I get close to max with IMR 8208 XBR I am getting flattened primers, deep firing pin strikes and even a couple pierced primers. There is another thread here and the OP posted pictures, some of my primers look exactly like his from his Liberty Barrel. He marked up his loaded round and chambered it, showing it was rubbing on the bullet. Whether from a rough chamber, short neck, tight neck whatever, I don't care to get into the Liberty debate. Anyway I marked up on my 123 gr SST loads and its not marking. There is one really light rub mark that didnt go through the marker and that maybe from when I dropped the bullet extracting it.
Here are some progressively hotter loads.

ETA that center primer was a Remington Benchrest Primer, I think they are softer? I am thinking that is why it flattened more, but the firing pin strike was not as deep
The last one is about .2 grs under max

This is a picture of the bullet I marked up it looks the same all the way around, though it does not show up this is the side with the light rub mark.



There is not an adjustable gas block made that will work with my barrel and forearm. I have not been able to bring myself to paying 155 dollars for a buffer and spring so I have not tried Slash's heavy rifle buffer yet. Some one suggested I try putting lead shot in my buffer instead of the weights. This made things worse. So maybe the heavy buffer is the correct way to go as the shot probably was not providing enough of a buffering effect. Any ideas? I was really hoping I would see a mark on the bullet I have custom rifle builder up the road that would have quickly fixed that for me.

[customcutter]

IIRC someone put some .45 bullets in their buffer. The lead shot may have too much space between the shot get the weight you need.

[bwaites]

You are probably experienced enough to know that not every rifle has the same max load. Find the accuracy node below max load and load that!

[NugginFutz]

As I recall, some of the Horde have mentioned that with 8208, it can really sneak up on you, so caution is definitely suggested while you work up your loads.

I don't know what barrel configuration you have, but I have a 22" RLGS BHW Bull Barrel, with a BTE adjustable base block. I had some over gassing issues with some loads, and this block worked well. I mention BTE, because I've read several times where the owner, George, has been known to accommodate other heavy barrel customers by milling the blocks down to a lower profile. He is also one of the few sources where I could get an adjustable gas block for a .936" barrel.

Just a suggestion.

[MTNmyMAG]

Ahh yeah I should have mentioned that, its a 24" barrel. It has a .936 gas block journal, I had the rest of the barrel profiled down. I may end up redoing it again.

[MTNmyMAG]

You are probably experienced enough to know that not every rifle has the same max load. Find the accuracy node below max load and load that!

Yes sir I understand that, but I have specific expectations for this rifle and I am working to make it meet them before I start using the barrel for a cheater pipe. I am going to try CFE223 and I guess the heavier buffer, the .264 LBC has a tighter throat but a longer leade I think? Would re-reaming with a Grendel reamer be a bad idea? I am just not going to settle for velocity in a 24" barrel that is slower than what people are getting with an 18" or even 16".

[NugginFutz]

I think that running a Grendel reamer in the 264 LBC chamber would open up the neck clearance a bit, but it wouldn't result in the same compound throat that the SAAMI Grendel has. Would it be a bad idea? I can't say, but it clearly would be a hybrid chamber, if you do.

As far as velocities go, my "Type II" 22" BHW is getting 2600 fps, with Hornady cases, 450 primers, with 28.2 grains of 8208 pushing a 123 A-Max. IIRC, they're seated at 2.250", but I'd need to check my logbook.

I've been reading some wonderful things about the results and consistency some of the Horde are getting with CFE223. I've even heard that burned CFE223 powder smells like unicorn farts. I'm quite tempted to run up a load on it and see how it does in mine. After I go through the keg of 8208, that is.

[MTNmyMAG]

I am getting like 2438 IIRC in my 24" before I start seeing pressure signs, early unlocking was been suggested by quite a few people.

[Drifter]

I am getting like 2438 IIRC in my 24" before I start seeing pressure signs...

How much neck tension, and do you crimp?

If you're using an s-type die, what size bushing?

BHW has offered barrels headspaced for Type 1 and Type 2 bolts. Are you sure that you're using the correct bolt?

[Tedward]

As I recall, some of the Horde have mentioned that with 8208, it can really sneak up on you, so caution is definitely suggested while you work up your loads.

I don't know what barrel configuration you have, but I have a 22" RLGS BHW Bull Barrel, with a BTE adjustable base block. I had some over gassing issues with some loads, and this block worked well. I mention BTE, because I've read several times where the owner, George, has been known to accommodate other heavy barrel customers by milling the blocks down to a lower profile. He is also one of the few sources where I could get an adjustable gas block for a .936" barrel.

Just a suggestion.

I was just curious and they do have low profile (micro) Adj. GB for .936 in stock. Some decent prices there too on a few other things.
http://bte-usa.com/parts/set-screw-micro-gasblocks.htm

[MTNmyMAG]

How much neck tension, and do you crimp?

If you're using an s-type die, what size bushing?

BHW has offered barrels headspaced for Type 1 and Type 2 bolts. Are you sure that you're using the correct bolt?

I haven't measured to see, I bought it new second hand. The guy said the bolt came with it from BHW. It is a typeII bolt. No I am not crimping

[Drifter]

I haven't measured to see, I bought it new second hand. The guy said the bolt came with it from BHW. It is a typeII bolt.

Here's a vid that might help:

[video=youtube;DZncepUMgBg]http://www.youtube.com/watch?v=DZncepUMgBg[/video]

[SG4247]

8208 is a very unique powder. I went up to 28.4 in my 22" LBC
chamber and had no pressure signs with 123 Amax and Hornady brass.

I ONLY use CCI #41 primers in semi auto guns. Lessons learned from issues like yours.

I did not expect that at lower powder loads 8208 would barely extract the rounds. As I went up on powder toward 28.0 it started to function properly. Velocity seems good with 8208 and 123s but no real velocity improvement when I went beyond 28.0.

I now understand why people say 8208 is for short barrels and light bullets....

[GLShooter]

George makes an adjustable that will fit or will make one. A call would be in order. All of my REM7 1/2 BR primers are brass. I haven't seen a silver one in over ten years. Dropping a reamer in that chamber would not do a thing for performance. Way to many of these barrels shoot lights out. It could just be a preference of your tube. Look at RL15 and CFE. Check the distance to lands and don't jam them at this point. Some speeds would nice to have. The GB will cut down swipes etc and let you save some bucks. I can tell you that BHW barrels like it hot.

Greg

[MTNmyMAG]

George makes an adjustable that will fit or will make one. A call would be in order. All of my REM7 1/2 BR primers are brass. I haven't seen a silver one in over ten years. Dropping a reamer in that chamber would not do a thing for performance. Way to many of these barrels shoot lights out. It could just be a preference of your tube. Look at RL15 and CFE. Check the distance to lands and don't jam them at this point. Some speeds would nice to have. The GB will cut down swipes etc and let you save some bucks. I can tell you that BHW barrels like it hot.

Greg

I'll have to look I am pretty sure the middle one is a rem 71/2 I bought them in 2007. The barrel shoots fine, 5/8ths 5 round groups

[MTNmyMAG]

8208 is a very unique powder. I went up to 28.4 in my 22" LBC
chamber and had no pressure signs with 123 Amax and Hornady brass.

I ONLY use CCI #41 primers in semi auto guns. Lessons learned from issues like yours.

I did not expect that at lower powder loads 8208 would barely extract the rounds. As I went up on powder toward 28.0 it started to function properly. Velocity seems good with 8208 and 123s but no real velocity improvement when I went beyond 28.0.

I now understand why people say 8208 is for short barrels and light bullets....

I had to back down to 27.3 grs. One of the things that puzzles me is in my initial work up I didn't have pressures signs at 28.5

[MTNmyMAG]

Ill have to strip my bolt and try it, I do not have any loaded factory ammo though. My bolt is not marked with a 1 or 2. I measured it though and it is a type 2 bolt I am starting to think this is my issue.