CA ridgeline FFT clambering question..

[snopro176]

I took this new gun to the range last weekend and noticed I could barely get the bolt closed on a round that was coal of 2.950, which should be .005 under saami speck. I measured today and found my chamber is 2.945"? Am I missing something? I thought saami was what all these OTC rifles are chambered to?

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[Harvey_NW]

If you are jamming the lands with anything but a round nose at SAAMI COAL something definitely seems wrong, you should have plenty of freebore. What caliber, and bullet are you using?

 

[snopro176]

If you are jamming the lands with anything but a round nose at SAAMI COAL something definitely seems wrong, you should have plenty of freebore. What caliber, and bullet are you using?

It's a 6.5prc with a 127 barnes lrx

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[Harvey_NW]

The chamber, reamer, and cartridge dimensions all vary a little bit due to tolerances for clearance. To measure your jam or land contact point as accurately as possible with common tools you need to measure off the bullet ogive with a comparator. But unless I'm missing something as well, I wouldn't think a 127 LRX loaded to SAAMI COAL dimension would jam the lands. The only thing I can think of is possibly a carbon ring or buildup issue. Interested to hear input from others with more knowledge.

The one question I have is how did you come up with your mentioned chamber measurement?

 

[snopro176]

The chamber, reamer, and cartridge dimensions all vary a little bit due to tolerances for clearance. To measure your jam or land contact point as accurately as possible with common tools you need to measure off the bullet ogive with a comparator. But unless I'm missing something as well, I wouldn't think a 127 LRX loaded to SAAMI COAL dimension would jam the lands. The only thing I can think of is possibly a carbon ring or buildup issue. Interested to hear input from others with more knowledge.

The one question I have is how did you come up with your mentioned chamber measurement?

I don't have the tool your supposed to use but an old timer taught me awhile ago how to use a dowel. Run a dowel down the barrel until it hits the bolt face and mark it with a band of tape right up against the end of the muzzle. Then drop the bullet you intend to use down the back of the action until it wedges in the lands, then a LIGHt tap on the back of it with that dowel to ensure it doesn't pop back into the action when you re measure. Now take that same dowel and gently insert it until it just touches the tip of your bullet, mark it with another tape band the. Measure between the 2 bands with your calipers. It's not perfect but I'd bet its within .003". I wasn't looking for a hard number really but my 2.945 does appear accurate since 2.950 was engaging the lands.

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[ResearchinStuff]

given the manufacturer, yeah, the chamber is probably jacked up in some way shape or form.

 

[Patterbuilt]

I had one (ca ridgeline) in 30/06. Trying to break in the barrel and had some factory loads that required a little to much force to close the bolt. Tried to unload the rifle and it pulled the bullet frame the case!!! I hear they are better now, but have no further experience

 

[JakeSCH]

How confident were you that it was actually engaging lands? Was the bullet marked by the rifling? CA is known for having really tight chambers for their 6.5 prc, I would assume that is the case for you as well.

Take a piece of (unloaded) brass and try to close the bolt. If that is really smooth then I would also check it compared to a loaded round, measuring diameter, looking at the shoulders, etc.

 

[snopro176]

How confident were you that it was actually engaging lands? Was the bullet marked by the rifling? CA is known for having really tight chambers for their 6.5 prc, I would assume that is the case for you as well.

Take a piece of (unloaded) brass and try to close the bolt. If that is really smooth then I would also check it compared to a loaded round, measuring diameter, looking at the shoulders, etc.

It was definitely engaging. I've got about 122 rounds down it now, 1 trip through all 100 pc's of brass and this is the first time I've ever had a piece of fired brass not be able to slide a bullet into. The fired brass still has just enough neck tension to keep you from being able to push a bullet in. This is peterson brass with a turned .014" neck. Seems tight

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