Heavy Bolt lift on Tikka 6.5

[ElPollo]

I agree that the OPs’s problem is likely related to an issue with the ammo. I haven’t cleaned a centerfire rifle bore in six years and have one suppressor with more than 2500 rounds through it that has never been cleaned. Never seen a problem chambering ammo or accuracy in a factory barrel. Only once in a custom barrel that had a tight chamber, but that was not an intermittent problem. It did it all the time with several factory loads, but some worked fine. If you’re seeing this issue with the same ammo that previously worked fine, I’d try a different lot of the same ammo.

I cannot imagine cleaning a suppressor every 100 rounds. Man, OCD is a thing and it’s a fun-killer. If I had to do that, I’d take up a different hobby.

 

[Jake Larsen]

In back to back lot numbers of Hornday 6.5cm ELD-M’s match we had a difference of almost 200 fps higher MV, with the resulting issues one would expect from nearly 6.5 PRC muzzle velocities.

I’m sure some would have said it was the dreaded “donut”.

You think it’s different lots of powder causing the MV changes? Hard to imagine Hornady would tweak the load in their factory ammo without making an announcement.

I’ve never been a factory ammo shooter, but I guess you’d need to make sure everything you’re using is from the same lot, and re-check zero/MV when switching to a new lot.


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[nephewjephew]

To get back on topic a bit. I don't know if it is a "carbon ring" or not, it was just the first suggestion.

You said that you switched boxes, was it the same lot # of ammo?

I have seen lots vary by almost 200fps.

Looked though some notes and there's 356 rds on the gun through 3 different lots 40, 100, 216 rounds (all 147 eldm) in that order. Started a fresh box when the issue started and grabbed a different box that was previously shot (same lot). 16 rds total that day with that gun and maybe 6 rounds with a problem. My first thought was ammo, so I will pick up new box to see if its repeatable. If it continues with new ammo then maybe there's a deeper problem.

I like shooting guns I don't enjoy cleaning guns, I'm lazy in that regard. And I haven't had a problem with not cleaning for years now. I don't understand the apprehension from some people that are so opposed to ideas or process that are so easy to see if they work or not, some of these things are really easy to test yourself.

 

[jamesmc8]

Lots of Powder, even in the extreme line can vary in velocity too. Varget is one of the more stable powders. However when I switched to a new lot with some 6 ARC loads I lost 60 fps. Nothing else was changed and shot over a Garmin.

 

[Formidilosus]

You think it’s different lots of powder causing the MV changes? Hard to imagine Hornady would tweak the load in their factory ammo without making an announcement.

Yes. They absolutely use different powders between lots. Since 2020 or so companies have had to use whatever powder they can get their hands on.

I’ve never been a factory ammo shooter, but I guess you’d need to make sure everything you’re using is from the same lot, and re-check zero/MV when switching to a new lot.

This is exactly what one has to do. Lot to lot variation is a thing, and often enough it is not a small difference.

Having said that, there are some ammo brands/liens that are stable lot to lot- Federal Gold Medal Match for instance.

 

[Formidilosus]

Looked though some notes and there's 356 rds on the gun through 3 different lots 40, 100, 216 rounds (all 147 eldm) in that order. Started a fresh box when the issue started and grabbed a different box that was previously shot (same lot). 16 rds total that day with that gun and maybe 6 rounds with a problem. My first thought was ammo, so I will pick up new box to see if its repeatable. If it continues with new ammo then maybe there's a deeper problem.

It is low odds that it is from not cleaning, it could be debris in the chamber, but odds are it’s not. While for most not cleaning may be a novel idea, there are places that fire pallets of ammo a week, that do not clean at all, without issue.

The highest probability is that you have a lot, or lots that are on the hotter side of average.

I don't understand the apprehension from some people that are so opposed to ideas or process that are so easy to see if they work or not, some of these things are really easy to test yourself.

Because experimenting would require shooting and very few people do that. Doing so would remove the myth and lore surrounding it all.

 

[SDHNTR]

Uggh, again?

Cleaners vs non cleaners
.223 vs .30 cal guys
Monos vs fragmenting lead
Form posse vs everyone with opposing views

There’s a time and a place for all of it. There are no absolutes in the field. There’s value in both sides of an argument. The attitude of I’m always right and you’re wrong is off putting and this pace is beginning to circle the drain because of it. It gets old.

Can’t we just go hunting? Where are the hunting stories? Hunting is interesting and fun, arguing over carbon build up is not.

 

[Formidilosus]

Uggh, again?

Cleaners vs non cleaners
.223 vs .30 cal guys
Monos vs fragmenting lead
Form posse vs everyone with opposing views

There’s a time and a place for all of it. There are no absolutes in the field. There’s value in both sides of an argument. The attitude of I’m always right and you’re wrong is off putting and this pace is beginning to circle the drain because of it. It gets old.

Can’t we just go hunting? Where are the hunting stories? Hunting is interesting and fun, arguing over carbon build up is not.

You know that you don’t have to click on technical threads.

The story forum is here-

Rokslide Live Hunt/Hunting Stories

Share your live hunts and hunting stories here.

rokslide.com

 

[nephewjephew]

It is low odds that it is from not cleaning, it could be debris in the chamber, but odds are it’s not. While for most not cleaning may be a novel idea, there are places that fire pallets of ammo a week, that do not clean at all, without issue.

The highest probability is that you have a lot, or lots that are on the hotter side of average.

That is my gut reaction too. I have shot 200 rounds of that lot with no issue and have 300 of that lot left. Can there be that much variance within a lot?

 

[Formidilosus]

That is my gut reaction too. I have shot 200 rounds of that lot with no issue and have 300 of that lot left. Can there be that much variance within a lot?

Generally no. But, that lot could be right on the edge, and then yes- some debris or fouling could cause issues. If that’s the case, scraping the chamber might reduce pressure issues for a bit, but they’ll come back.

 

[justin davis]

I’d venture to guess that it is the ammo. Something different with the lot.

 

[5811]

That is my gut reaction too. I have shot 200 rounds of that lot with no issue and have 300 of that lot left. Can there be that much variance within a lot?

I bought some early production hornady 7mm prc that would give me a stiff bolt lift intermittently. They have since switched powders and it's a non issue, so my experience is the reverse of yours.

 

[mxgsfmdpx]

Uggh, again?

Cleaners vs non cleaners
.223 vs .30 cal guys
Monos vs fragmenting lead
Form posse vs everyone with opposing views

There’s a time and a place for all of it. There are no absolutes in the field. There’s value in both sides of an argument. The attitude of I’m always right and you’re wrong is off putting and this pace is beginning to circle the drain because of it. It gets old.

Can’t we just go hunting? Where are the hunting stories? Hunting is interesting and fun, arguing over carbon build up is not.

This is a thread trying to help someone resolve an issue. Simply move onto the next thread instead of taking time out of your day to frustrate yourself.

Only you have the power to not click on it, get upset, and then take time to type and whine.