Suppressors - first round impact shift

[hibernation]

Man, that 30 cal can to baffle scraping on a 223 would tell me that can is either WAY out of whack, or the muzzle threads are not concentric to the bore, that's a 340 ID catching a 224 bullet diameter.

It almost certainly would've been the 7mm-08 that caused that, that's the first rifle I used it with.

 

[Chris_in_Idaho]

That makes more sense than the .223, but still, .284 should have had quite a margin.

 

[hibernation]

Update: finished some more thorough testing and am now confident that there are no issues with it, at least on this rifle. I'm basing this on 6 separate 3-shot groups all fired on separate days from a completely cold bore. So, every time I was out I'd shoot a string of 3 at 100yds on separate targets. Measured them all out, plotted in excel, went overboard with some stats, and any variation by shot order seems to be just due to chance. Here's what the 18-round spread looks like (Tikka 223, 16" barrel w/ Diligent LTi, Hornady 55gr SP):



Extreme spread is 1.9", mean radius 0.5". Seems reasonable for inexpensive ammo and a mediocre shooter. Lots and lots of washboard gravel roads between each group, so this is also reassuring for zero retention at least.

Since I had all the shot locations in excel, I also wanted to look at round count vs. zeroing. This next figure is what my total adjustment in mils would be as round count increased. Nothing groundbreaking but it does confirm what everyone has been saying lately, by 10 rounds I'm within a click. I'll continue to use a 10-round zero.



Maybe Diligent fixed the issue when I sent it in, maybe it was unique to one rifle/suppressor combination, maybe I just suck and jumped to conclusions off a few bad/random shots. My takeaway is I need to keep better data, especially with new setups.

 

[longrange13]

Update: finished some more thorough testing and am now confident that there are no issues with it, at least on this rifle. I'm basing this on 6 separate 3-shot groups all fired on separate days from a completely cold bore. So, every time I was out I'd shoot a string of 3 at 100yds on separate targets. Measured them all out, plotted in excel, went overboard with some stats, and any variation by shot order seems to be just due to chance. Here's what the 18-round spread looks like (Tikka 223, 16" barrel w/ Diligent LTi, Hornady 55gr SP):

View attachment 894074

Extreme spread is 1.9", mean radius 0.5". Seems reasonable for inexpensive ammo and a mediocre shooter. Lots and lots of washboard gravel roads between each group, so this is also reassuring for zero retention at least.

Since I had all the shot locations in excel, I also wanted to look at round count vs. zeroing. This next figure is what my total adjustment in mils would be as round count increased. Nothing groundbreaking but it does confirm what everyone has been saying lately, by 10 rounds I'm within a click. I'll continue to use a 10-round zero.

View attachment 894087

Maybe Diligent fixed the issue when I sent it in, maybe it was unique to one rifle/suppressor combination, maybe I just suck and jumped to conclusions off a few bad/random shots. My takeaway is I need to keep better data, especially with new setups.

Nice data, thanks for sharing.

 

[eli425]

Was searching for dd wolf hunter issues and seems like this is the place to share.

Ive been running this can on my 22creedmoor for a good bit. Hunted with it and all. I only use the 80gr factory ammo for now. No issues up until just recently. Went to the range yesterday/today and my cold bore shift was drastic. I was able to repeat it several times. Shot a group, and then let it sit for a good bit.

The cold bore shift was repeated in terms of it happening but each time the shift was different. And I'm not talking about 1 or 2 moa. More like 7 moa. See picture of final result.

What I regret not doing was a zero/group without the can to confirm it is indeed the can. So I'll follow up in a week or so with another attempt.

Going to run the van through a sonic cleaner and see if that helps as well.

 

[justin davis]

Was searching for dd wolf hunter issues and seems like this is the place to share.

Ive been running this can on my 22creedmoor for a good bit. Hunted with it and all. I only use the 80gr factory ammo for now. No issues up until just recently. Went to the range yesterday/today and my cold bore shift was drastic. I was able to repeat it several times. Shot a group, and then let it sit for a good bit.

The cold bore shift was repeated in terms of it happening but each time the shift was different. And I'm not talking about 1 or 2 moa. More like 7 moa. See picture of final result.

What I regret not doing was a zero/group without the can to confirm it is indeed the can. So I'll follow up in a week or so with another attempt.

Going to run the van through a sonic cleaner and see if that helps as well.

Interesting

 

[hibernation]

What I regret not doing was a zero/group without the can to confirm it is indeed the can. So I'll follow up in a week or so with another attempt.

Going to run the van through a sonic cleaner and see if that helps as well.

Yeah, keep us posted with more data. Real interesting. If you've got access to a borescope, try looking through the can and checking for graze marks along the baffle edges. Checking the alignment with a bore rod isn't a bad idea either.

 

[5811]

Was searching for dd wolf hunter issues and seems like this is the place to share.

Ive been running this can on my 22creedmoor for a good bit. Hunted with it and all. I only use the 80gr factory ammo for now. No issues up until just recently. Went to the range yesterday/today and my cold bore shift was drastic. I was able to repeat it several times. Shot a group, and then let it sit for a good bit.

The cold bore shift was repeated in terms of it happening but each time the shift was different. And I'm not talking about 1 or 2 moa. More like 7 moa. See picture of final result.

What I regret not doing was a zero/group without the can to confirm it is indeed the can. So I'll follow up in a week or so with another attempt.

Going to run the van through a sonic cleaner and see if that helps as well.

Hard to think of anything internal to the suppressor that would have changed from no issue to big issue unless it sounds like a maraca.

Action screws and scope mount tight? Barrel tight?

 

[eli425]

Hard to think of anything internal to the suppressor that would have changed from no issue to big issue unless it sounds like a maraca.

Action screws and scope mount tight? Barrel tight?

Yeah for sure! My thoughts exactly. I double checked the scope and action screws.
I removed it for cleaning and noticed theres something moving around in there when I shake it violently. Not like maracas, but still something.
So I ran it through the sonic cleaner, rinsed it off, and used compressed air to get everything out. Sound with shaking went away, which gives me hope. I went through the cleaner but didnt find any obvious debris. Just a ton of melted down carbon.
I'm waiting on more ammo to come in and another day. I'll report back after my next range trip.

Assuming thats the issue, begs the question, can a small amount of foreign matter cause stuff like this? Lets say it was some clumped up carbon or something. Would that really cause wild impact shifts, specifically on cold bore shots? I'm trying to think through it and to me it seems like if thats the case, its floating around freely while cold, and then gas from first shot nails it down to one spot and then it stays tight after that?

 

[hibernation]

I removed it for cleaning and noticed theres something moving around in there when I shake it violently. Not like maracas, but still something.

I noticed the exact same thing with my LTi. It was gone when it came back from Diligent, I've wondered if it had anything to do with it.

 

[eli425]

Did the issue go away when you received it back from them? What did they say it was?

 

[hibernation]

Yeah, I'll update the original post so it's up top, but they checked it out and said they "straightened it up a little". I assume they cleaned it too since that light rattle was gone, and test fired since it came back with a different rear hub adaptor mounted (in addition to the one I had on there). Not exactly a detailed explanation, but their CS was really impressive, they shipped it back fast, and followed up later on to see if it was shooting straight. I haven't had any issues since then.

 

[5811]

Yeah for sure! My thoughts exactly. I double checked the scope and action screws.
I removed it for cleaning and noticed theres something moving around in there when I shake it violently. Not like maracas, but still something.
So I ran it through the sonic cleaner, rinsed it off, and used compressed air to get everything out. Sound with shaking went away, which gives me hope. I went through the cleaner but didnt find any obvious debris. Just a ton of melted down carbon.
I'm waiting on more ammo to come in and another day. I'll report back after my next range trip.

Assuming thats the issue, begs the question, can a small amount of foreign matter cause stuff like this? Lets say it was some clumped up carbon or something. Would that really cause wild impact shifts, specifically on cold bore shots? I'm trying to think through it and to me it seems like if thats the case, its floating around freely while cold, and then gas from first shot nails it down to one spot and then it stays tight after that?

Definitely an interesting thought. Are you standing the rifle up between strings? Is the rear hub mount tight? Threads good? Did you remove the hub and the cap to clean?

 

[eli425]

Definitely an interesting thought. Are you standing the rifle up between strings? Is the rear hub mount tight? Threads good? Did you remove the hub and the cap to clean?

No I lay it down on its side, bolt open to cool faster.
Yeah I do a quick check to make sure it's all tight before shooting.
I have a banish 30 that would consistently loosen up after a few shots on a 300wsm so I'm low key paranoid about that all the time.

Yes I removed the hub to clean. I didn't touch the end cap. Not sure if that's supposed to come off on the wolf hunter?

I think next range trip if it's still doing the same thing I'ma try the same process with the banish and see if it's can or rifle.

 

[eli425]

No I lay it down on its side, bolt open to cool faster.
Yeah I do a quick check to make sure it's all tight before shooting.
I have a banish 30 that would consistently loosen up after a few shots on a 300wsm so I'm low key paranoid about that all the time.

Yes I removed the hub to clean. I didn't touch the end cap. Not sure if that's supposed to come off on the wolf hunter?

I think next range trip if it's still doing the same thing I'ma try the same process with the banish and see if it's can or rifle.

Wanted to leave a follow up here:
Had the can through the sonic cleaner couple rounds. Removed a bunch of chunks of carbon build up.

First cold bore shot after cleaning = on target. Proceeded with a solid 10round group.

Let it cool, shot it again, first round was off like before. Pulled the can off, opened it up and looks like a lot of carbon that was loosened up post cleaning, came out to the bottom. Emptied it out and let it sit till completely cool.

Shot again, no cold bore shift.

Let it cool completely, shot again, no cold bore shift.

Seems to have done the trick.

So essentially the cleaning took it from a cold bore shift of 7 moa to none perceivable.

I guess 300ish rounds of 22cm needs a cleaning from time to time. I'll keep tracking it in the coming months to see if it comes back!

 

[hibernation]

Let it cool, shot it again, first round was off like before. Pulled the can off, opened it up and looks like a lot of carbon that was loosened up post cleaning, came out to the bottom. Emptied it out and let it sit till completely cool.

I'm going to keep an eye on mine, I just pulled it off after ~100 rounds of shooting and heard that same light noise of a piece of carbon rattling around inside. Sounds like that's the culprit, not sure how to go about testing or preventing that though. Take it off regularly to check? Clean more often?

 

[eli425]

I'm going to keep an eye on mine, I just pulled it off after ~100 rounds of shooting and heard that same light noise of a piece of carbon rattling around inside. Sounds like that's the culprit, not sure how to go about testing or preventing that though. Take it off regularly to check? Clean more often?

Yeah I dont know. I don't want to have to worry about constantly cleaning it and checking to see if my cold bore decided to shift after an unknown number of rounds you know? Not sure what the ideal solution is. But I think I'll just run it as usual, keep checking for cold bore shifts on range days and do a good cleaning before any major hunts.