Help me out, tuning with a can

[Bc'z]

Did you start off by picking a load, then shoot with/without can? You should only see POI shift, the group should be same or maybe better with can on. This is simply about eliminating the can as a potential problem up front, they are not all created equal.

Can has been on through the the tuning sessions. Going by if 2 ain't touching 3 ain't getting any better here's the seating test. This is 49gr N565 right smak in the middle of Vhit load data.
It wants to shoot, we're gonna do bushings above and below the .288 used for initial development. I don't have the charge weight test shot in OCW format, I'll get Devon to forward or post a picture.
I did notice his crown was caked in carbon, and instructed him to clean it and the can despite manufacturers statement of 20k rounds.
I thought that was an odd statement for the manufacturer to make.
Personally I feel guns are supposed to be loud

 

[jxb]

Can has been on through the the tuning sessions. Going by if 2 ain't touching 3 ain't getting any better here's the seating test. This is 49gr N565 right smak in the middle of Vhit load data.View attachment 1576279
It wants to shoot, we're gonna do bushings above and below the .288 used for initial development. I don't have the charge weight test shot in OCW format, I'll get Devon to forward or post a picture.
I did notice his crown was caked in carbon, and instructed him to clean it and the can despite manufacturers statement of 20k rounds.
I thought that was an odd statement for the manufacturer to make.
Personally I feel guns are supposed to be loud

It wanting to shoot wasn't my point as I assumed it would both with/without, just I'd make sure it keeps roughly the same group size with/without can on and only change is POI. Of course for some reason I was assuming this was a hunting rifle and that's why. Never know in the field if you need to shoot without the can so I just go prepared for either.

 

[Bc'z]

It wanting to shoot wasn't my point as I assumed it would both with/without, just I'd make sure it keeps roughly the same group size with/without can on and only change is POI. Of course for some reason I was assuming this was a hunting rifle and that's why. Never know in the field if you need to shoot without the can so I just go prepared for either.

It will go to the woods mostly as a sit on a landing and glass the cuts typ of hunting, but mostly used as a range rifle.
Here's the OCW test
Ugly ain't it!!

 

[Straightshooter1]

I've got H4350 and 4831sc on hand as well. Was just hoping he didn't have to get into $60 a pound for powder.
I just got off the phone with Zack and he enlightened me on the cartridge a bit and suggested faster powder.

Here's what I got with that 53.9 grs of H4831sc when adjusting the tuner for a good setting:

 

[nakneker]

Sean I just got off phone with Devon discussing the information I've gleaned in the last 18 hours.
Looking at his seating test I'm thinking of tension test before increasing charge, my thought is if his rifle wants higher tension we should find this out 1st before before maxing out charge and winding up in a over preasure situation.
@JB10 sent me the info from Berger for the 140gr, I'll forward it to you.
Verry interesting the spread in powders used In thier data.
Devon is probably gonna be getting one of those ODCR rifles we love so much before too long

Recieved and thank you!

 

[jxb]

It will go to the woods mostly as a sit on a landing and glass the cuts typ of hunting, but mostly used as a range rifle.
Here's the OCW testView attachment 1576301
Ugly ain't it!!

Um I'm thinking more like deplorable. Yeah that's pretty ugly alright.

 

[snert]

I am surprised someone didn't say this already but

you can tuna guitar but you can't tuna fish..maybe you can tuna can?

 

[snert]

Sorry, it's late and Im punchy...

 

[jxb]

on carbon and cleaning. I only clean the threads or other contact areas then apply a little anti-seize grease to the threads before using it next time. When I was talking to the TBAC folks they said many people weigh the can new and note, then once it reaches n+x clean it. In my case I can send to them once a year for a free cleaning and inspection if I wanted to. Then he said, I shoot mine all the time in competition and I never clean it, the carbon builds up and over time flakes off so it's more about shake out any loose carbon before/after use. Keep in mind I think they are shooting to 1moa steel, maybe 1/2moa.

I have noticed the same on mine that I use on four different rifles, none have changed group to speak of with it not being cleaned. All four shoot the same group size with/without can, some slightly better with can. POI changes on each rifle with/without, some a little <1", some more 2-3", and one a whopping six inches. In all cases it's consistent so I simply note the poi shift for each and use them. Some I zero with can, others without so I of course note that on the poi shift doc.

Anyhow, please keep posting, I'm all set and enjoying the progress and comments.

 

[ricco1949]

@jxb

"All four shoot the same group size with/without can, some slightly better with can. POI changes on each rifle with/without, some a little <1", some more 2-3", and one a whopping six inches."

I recently read that alternating the turbulence hole alignment may minimize POI shift without material effect on can decibels. I haven't tried it yet but it may be worth a try on your cans.

There is a separate U-Tube demonstrating the alignment decibel effect.

 

[Tucker65]

I've built a handful of 6.5 PRC's for hunting purposes. All of them were built with 7.5 twist barrels and a 156gr Berger was the bullets that were used. ADG or Lapua brass was used along with CCI 250 prrimers. The first coupe of rifles we used Reloader 26 and best accuracy was right at the 3000 fps mark. When that powder became hard to find we switched to N565. We could reach the same velocity but but the groups opened up at that speed. We backed it down a little and the accuracy was right around 2960 -2975 with the N565. These rifles all had 24" carbon wrapped barrels, either Proof Research or Benchmark. You might just need to up the charge as you're running quite a bit less than what I found worked in the rifles I played with using heavier bullets.

 

[falconpilot]

Going to ask a dumb question as I've seen this before...Did the rifle have a break on it from factory? If so, are you 100% sure that the shim was removed before screwing can on? I know it sounds stupid, but they are easily missed if they've been tighted down flat. I've seen them cause this issue before..

 

[Bc'z]

Going to ask a dumb question as I've seen this before...Did the rifle have a break on it from factory? If so, are you 100% sure that the shim was removed before screwing can on? I know it sounds stupid, but they are easily missed if they've been tighted down flat. I've seen them cause this issue before..

I will check, I was just getting ready to give Devon a call.
I'm going to grab his brass and set up a charge ladder with a faster powder, along with the N565 working off of the Berger load data.

Edit, just got off phone with him, washer is still in place.
Thank you @falconpilot

 

[Bc'z]

A little update...
Muzzle brake washer was in place last week, it is now removed.
I mopped chamber with alcohol to remove any lube, last week he failed to wype cases before testing, they were covered in 1 shot. I noticed this while I prepped the brass he had loaded.
I had him do a 2 shot charge test in OCW format today, not looking at groups just horizontal plane of poi and 3 shot bushing test.
I feel Devon shot a good load report this morning
I sent him back to range with 2 loads 3 rounds each
.288 bushing 57.7 charge
.289 bushing 57.7 charge
Waiting for him to return with next target, I believe we're getting somewhere.
56.5 had a difference of 4.5gr difference in brass weight, I'm thinking that's the lower shot.

 

[Bc'z]

Looks like we're done testing with N565, we very well may investigate a different powder in the future.
I'm leaning towards shooter error on the horizontal stringing.

 

[Coyotefurharvester]

I test without the can, as I haven't not found a good load that didn't get BETTER suppressed. Also gives me poi difference, keep this on my zero card. And I also note if removing/replacing the can gives a first shot zero error(traveling/hunting situation).

 

[JEFFPPC]

LMAO

 

[Bc'z]

LMAO

Curious as to what your finding amusing??
Devon has done a great job learning a process to load and tune for his own rifles, as I've learned quite a bit about tuning with a suppressor.
He's not an accomplished shooter but very new to seeking out precision and growing as a shooter and learning his gear which happens to be factory and not a custom.
So unless you have something positive to add I suggest you go sit in a corner and contemplate your response and think back to when you were a new shooter.
And while your there maybe say a prayer for all the men and women who wear a uniform to protect your freedoms to voice your silly opinions.
You should be giving him thanks, not childish attempts at humor.

Boy have I grown, I got all that out without telling you to pound sand.

Personally I'm not impressed with the cartridge but I know we can get more out of it. Powder selection will probably help a lot but had to go through the process and discuss it as we worked through this with his powder selection.
Devon has full access to my supplies of powder and primer for testing while he learns the process.

 

[Coyotefurharvester]

Bc'z, I remembered a situation during load development that had me looking back through some target notes. I had done a quick and dirty test with a 20p upper. Had a very respectable load with Nos 40 bt. While at the range for a confirmation group or two, decided to put the can on. Barrel was 1/2-28, but I didn't have that direct thread adapter with. So I used a 1/2-28 to 5/8-24 adapter between barrel and the can. Groups fall apart, from sub 1/2" @100 yards to 2+inches. I was new to the 20p, so I blamed myself(case/load technique). Actually stopped shooting and went home to figure out where I messed up. Loaded more of same load. Next range session, still had can on rifle. Another 2" ish group. Perplexed I pulled the can to shoot on a different rifle, saw the thread adapter. Light bulb came on. Had the actual 1/2-28 can direct thread with. Groups were ragged hole, minus the step up adapter.

 

[JEFFPPC]

Ok I should have said I see some comments that make me cry at how absurd they are.