108gr ELD-M tolerance issues

[SouthPaw]

Yea mine was from last year's fourth of July sale and I know of a couple other guys that had Tikka 6cm from them around the same with finicky chambers. they shot through it and never quite got as bad as mine. They made it right but it was still a pita, luckily my friend has all the tools to help me with it

Thank you for this. I got my Tikka 6cm barrel during that same sale last year and it's doing the same with my hand loads, plus spiking pressure. 250 rounds on it. Looks like I need to send it in, right before hunting season. What a huge pita.

 

[wind gypsy]

Agree that it looks like short freebore. Hornady put lots of freebore in their SAAMI spec. More than many folks shooting 105 bergers or similar want thus there are lots of reamers out there with shorter than SAAMI freebore.

Thank you for this. I got my Tikka 6cm barrel during that same sale last year and it's doing the same with my hand loads, plus spiking pressure. 250 rounds on it. Looks like I need to send it in, right before hunting season. What a huge pita.

4th of July sale or that 6mm group buy sale? I have a backup barrel still sitting in the safe from the 6mm group sale that hasn't been shot yet.. Would like to verify all is good as i was considering selling it and dont want to send someone a problem.

 

[Lawnboi]

I wonder if someone got the short fb mixed up with the 6 creed standard.

The short freebore reamer is great for berger hybrids.

 

[pods8 (Rugged Stitching)]

Is the reason the FB issue is coming up after X rounds due to carbon build up? Versus always there.

 

[wind gypsy]

Agree that it looks like short freebore. Hornady put lots of freebore in their SAAMI spec. More than many folks shooting 105 bergers or similar want thus there are lots of reamers out there with shorter than SAAMI freebore.

Looking at this again, i'm not so sure i think its just short freebore.. Would have to be a VERY short freebore spec to scrape that close to the case mouth, basically zero. Is that scraping around the whole circumference of the bullet? The sharpie pics make it look like it's on one side which would indicate something like an off center chamber or other chamber defect. If it's the whole way around either the guy has an oddball reamer or it's cutting under spec freebore.

Weird thing is how wide that scraping is and there is no indication of different depths from land/groove transitions.

 

[BCsteve]

Weird thing is how wide that scraping is and there is no indication of different depths from land/groove transitions.

^^This?

 

[bojangles808]

Agree that it looks like short freebore. Hornady put lots of freebore in their SAAMI spec. More than many folks shooting 105 bergers or similar want thus there are lots of reamers out there with shorter than SAAMI freebore.


4th of July sale or that 6mm group buy sale? I have a backup barrel still sitting in the safe from the 6mm group sale that hasn't been shot yet.. Would like to verify all is good as i was considering selling it and dont want to send someone a problem.

4th of July freedom from the crown sale

 

[Willie IV]

Looking at this again, i'm not so sure i think its just short freebore.. Would have to be a VERY short freebore spec to scrape that close to the case mouth, basically zero. Is that scraping around the whole circumference of the bullet? The sharpie pics make it look like it's on one side which would indicate something like an off center chamber or other chamber defect. If it's the whole way around either the guy has an oddball reamer or it's cutting under spec freebore.

Weird thing is how wide that scraping is and there is no indication of different depths from land/groove transitions.

it's basically around the whole circumference. Hard to tell what is from the insertion of the cartridge into the chamber and how much of it is due to the cam over of the bolt closing. His reamer isn't an oddball. I need to get it back to him for inspection.

 

[wind gypsy]

How many rounds have you fired? if the chamber isn't wonky the only other thing I can think of is a brutal carbon ring but I have a hard time believing one would be that bad.

 

[Willie IV]

How many rounds have you fired? if the chamber isn't wonky the only other thing I can think of is a brutal carbon ring but I have a hard time believing one would be that bad.

35 rds down this pipe. 15 shots first session and 20 the second session. Carbon cleaner in between. I cleaned because of the hard bolt close. I have a feeling I've got a few things going on. Likely "some carbon" and a match grade chamber fit that is just too tight for factory ammo tolerances. I went with a 6 creed to shoot the factory 108's as an easy button.

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[SouthPaw]

4th of July sale or that 6mm group buy sale? I have a backup barrel still sitting in the safe from the 6mm group sale that hasn't been shot yet.. Would like to verify all is good as i was considering selling it and dont want to send someone a problem.

2024 fftc 4th of July sale.

 

[SouthPaw]

4th of July freedom from the crown sale

Do you know which specific reamer they used on our barrels? Wondering if I can have my local guy fix it instead of shipping it back.

 

[bojangles808]

Do you know which specific reamer they used on our barrels? Wondering if I can have my local guy fix it instead of shipping it back.

It doesn't show on my reciept but I thought it was the PvA standard throat. I had told them I was going to shoot factory 108 eldms when I was sorting out what exactly I should order

 

[Lawnboi]

Maybe comment on snipers hide, the owner is on there regularly and I’m sure he would be interested in finding out what happened. There’s a fairly lengthy PVA thread that I started on there.

 

[mtnbound]

35 rds down this pipe. 15 shots first session and 20 the second session. Carbon cleaner in between. I cleaned because of the hard bolt close. I have a feeling I've got a few things going on. Likely "some carbon" and a match grade chamber fit that is just too tight for factory ammo tolerances. I went with a 6 creed to shoot the factory 108's as an easy button.

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Does the bolt close hard on a fired case?

 

[Willie IV]

Does the bolt close hard on a fired case?

Just got back from the gunsmith. Borescope showed a bit of carbon build-up, and the lead in was a touch shallow. We took it in an additional .0007 and it seemed to have fixed it with the 5 rounds we put down range. I need to get scope remounted and everything torqued again and send a bunch of rounds thru it. I feel confident after looking thru the borescope after the additional machining that we've got it resolved. I'll post tomorrow after a range day. I have a feeling carbon is gonna be an issue with this 6CM...

Thanks for everyone's comments on this.

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[wind gypsy]

Carbon is an issue after 35 rounds?! Hard seeing that. Is a smaller case than a 243.

 

[Gettin’by]

I’ve had this exact issue with Hornady Match 108’s over the last year. Multiple lot #s in three different barrels/chambers. They were all known good barrels with a few hundred rounds on them. It was a Hornady brass concentricity issue that was resolved via their warranty department. Contact them.

 

[Willie IV]

I’ve had this exact issue with Hornady Match 108’s over the last year. Multiple lot #s in three different barrels/chambers. They were all known good barrels with a few hundred rounds on them. It was a Hornady brass concentricity issue that was resolved via their warranty department. Contact them.

good to know. Too bad they're letting vendors keep this product on the shelf. I have 3 different lot numbers all purchased over the last 3 months. Every lot is doing this.

 

[Willie IV]

Carbon is an issue after 35 rounds?! Hard seeing that. Is a smaller case than a 243.

Borescope showed it. I'm not saying it was a full fledged carbon ring so bad that excessive pressure built but visually after 40 rounds we saw carbon build up starting.