Pressure Signs and Factory Ammo??

[River Reaper]

As I’ve come to understand pressure signs in a rifle (primers, ejector swipes, heavy bolt lift, etc.) I’ve learned that a rifle I have is experiencing pressure issues.

I can’t remember if it had these issues prior to getting suppressors. After getting a barrel forward suppressor and shooting a lot more though, I started noticing pressure with Sig Platinum Hunter ammo (heavy bolt, ejector marks, 140 Accubond).

I switched to factory ELD-M’s and if I remember correctly, I didn’t notice the pressure issues as much (however looking back at all the saved brass I have, a lot of them definitely have ejector marks).

I recently got an OG6.5 and shot at the range for the first time last night with factory Hornady 140 ELD-Ms. 16/20 shots all had ejector marks with heavy bolt lift, with some bolt lifts being heavier than others. It was 90 degrees outside, and I got an average of 2,687fps with the factory Hornady 140M out of a 22” barrel. 90 degrees is likely the hottest temp that I would hunt with this rifle, with it more likely being in the 20-60 degree range when it matters. I can’t remember if I saw these issues at cooler temps or during a hunt.

As a non-reloader, what do I do? Is it too tight of a chamber? Is it the suppressor? Probably a combo of both. I bought the suppressor specifically for main use on this rifle.

 

[mtnbound]

As I’ve come to understand pressure signs in a rifle (primers, ejector swipes, heavy bolt lift, etc.) I’ve learned that a rifle I have is experiencing pressure issues.

I can’t remember if it had these issues prior to getting suppressors. After getting a barrel forward suppressor and shooting a lot more though, I started noticing pressure with Sig Platinum Hunter ammo (heavy bolt, ejector marks, 140 Accubond).

I switched to factory ELD-M’s and if I remember correctly, I didn’t notice the pressure issues as much (however looking back at all the saved brass I have, a lot of them definitely have ejector marks).

I recently got an OG6.5 and shot at the range for the first time last night with factory Hornady 140 ELD-Ms. 16/20 shots all had ejector marks with heavy bolt lift, with some bolt lifts being heavier than others. It was 90 degrees outside, and I got an average of 2,687fps with the factory Hornady 140M out of a 22” barrel. 90 degrees is likely the hottest temp that I would hunt with this rifle, with it more likely being in the 20-60 degree range when it matters. I can’t remember if I saw these issues at cooler temps or during a hunt.

As a non-reloader, what do I do? Is it too tight of a chamber? Is it the suppressor? Probably a combo of both. I bought the suppressor specifically for main use on this rifle.

I would shoot the same ammo without a suppressor through the rifle, as you state you don't remember if you had issues before.

Can you post some pics of the brass showing the e-marks?

What is the rifle?

 

[Q_Sertorius]

My groups opened up from 1-1.5” to 2-3” 10 shots with the OG6.5 as well. Any thoughts?

Is it on tight?

 

[River Reaper]

Is it on tight?

Sorry they opened up on a different rifle (22arc) and my dad brain added it to this thread for some reason. This rifle with pressure issues is still shooting phenomenally and one of the most accurate I own, I’m just concerned with the pressure..

 

[River Reaper]

I would shoot the same ammo without a suppressor through the rifle, as you state you don't remember if you had issues before.

Can you post some pics of the brass showing the e-marks?

What is the rifle?

Here are a few with the e marks.



Rifle is a CA West River Mesa 6.5CM

 

[wind gypsy]

Welcome to some of the side effects of shooting suppressed.

Was there a head wind by chance when you were shooting?

3d printed cans also are subject to getting Ti dust in barrel back to action when new. I'd give your barrel a cleaning and wipe down the bolt, grease lugs too just to make sure that stuff isn't messing things up.

I can get high bolt thrust pressure signs with basically all of my standard higher backpressure cans when there is some humidity and a headwind after a limited # of shots then return another day with different conditions and not sniff a hint of pressure signs.

 

[Clayt6499]

I’ve actually ran into pressure issues before with Hornady factory ammo from their early runs of 300 PRC. Had really bad bolt lift issues. So it’s not as uncommon as you’d think. And as for Suppressor being the cause, I’m honestly fairly skeptical about that. Usually issues like pressure spikes are more rooted in things like Carbon ring buildup at your chamber end. When’s the last time you gave it a truly hard cleaning? Cause Carbon rings take a lot more effort to get out than regular fouling and they can absolutely lead to some very bad pressure issues

 

[River Reaper]

Welcome to some of the side effects of shooting suppressed.

Was there a head wind by chance when you were shooting?

3d printed cans also are subject to getting Ti dust in barrel back to action when new. I'd give your barrel a cleaning and wipe down the bolt, grease lugs too just to make sure that stuff isn't messing things up.

I can get high bolt thrust pressure signs with basically all of my standard higher backpressure cans when there is some humidity and a headwind after a limited # of shots then return another day with different conditions and not sniff a hint of pressure signs.

Yeah there was a slight headwind, kind of angled but there. Interesting.

Are ejector marks and occasional heavy bolt lift anything to worry about then? Or just monitor and if I eventually have to beat it open one day, then the issue is bad enough to take additional action?

 

[wind gypsy]

In regards of what to do as a factory ammo shooter - If it is occuring without a head wind and you're sure your chamber is clean/dry (no oils/solvents/moisture), you either need to find a lot of ammo that doesn't result in those issues, confirm if there is something with the chamber that is causing it, or live with it.

Take note of if it happens within your first few rounds. If it is only after a few when the back pressure/gases from can have changed chamber/bore condition it might be a lesser concern for hunting even if obviously not ideal.

Edit: in regards to the headwind issue, this is the first place I recall it being discussed in depth here: https://rokslide.com/forums/threads/suppressor-causing-chamber-condensation.367653/ . There is more talk about this phenomenon in other threads recently like the ones on S2h classes this spring and also one of the threads about the 22OG. I THINK often the pressure signs aren't necessarily pressure but rather bolt thrust from cases not gripping chamber walls. There typically isn't an increase in velocity to indicate higher pressure. It's still not a good thing. Hard on brass, hard on bolt lugs. I wouldn't accept constant sticky bolt lift, if you're fighting to lift your bolt all the time I wouldn't be surprised to end up with galled lugs.

 

[naked wombats]

Rifle is a CA West River Mesa 6.5CM

Are you able to measure the chamber?

If not, sharpie up a bullet, chamber and extract it, check for a ring towards the tip.

Christensen sometimes chambers shallow, my buddy has one that is into the lands, it has gone back to them and they have said its in spec. It does shoot lights out, so he hasnt throated it yet.