To clean or not to clean, that is the question.

[dombo3]

These are a few notes from my experience with my 6.5 PRC.

Disclaimer: This is a singular data point of one rifle. I have vastly less experience in hunting, shooting, rifles and reloading than the majority on this forum.

Backstory
I've just started reloading. Had some success with my 6.5x55 and 22 ARC bolt guns and decided to give the 6.5 PRC a nudge.

I intended just to seat the 147 eld-m to SAAMI COAL, but thought I would practice using the gear I've accumulated and make a few measurements. Seating depth I thought would be good practice. Unlike the Swede I am limited by magazine so SAAMI COAL was all I was aiming for but was interested in what jump measurement was.

Got the Hornady gear out and the bullet did not enter the lands anywhere near COAL of a factory round. hmmm. Tried several more times. Being a learner and having had some teething problems when I did this with the Swede and the ARC, I chambered a factory round to see what resistance I was getting. Was getting some resistance - see image below with the projectile getting damaged.

Google was my friend and suggested carbon ring. Teslong borescope arrived in the mail shortly later and the results of borescope investigation before and after cleaning are below.

Before clean

After cleaning

Chambered once fired brass during cleaning

Not getting scratches on factory round when chambering after the clean. Need to check the "jam" measurement again - during cleaning process was hitting lands slightly longer the factory COAL.

Cleaning: Used Bore Tech C4, Eliminator and Hoppes for cleaning. Bronze brush with C4. Took a lot of work. Used a 7mm bronze brush and focussed on the chamber area a lot within the cleaning process.

Other info - Round count. ~2-300. All factory loads.

The question now is: to clean or not to clean? I'm leaning towards regular maintenance cleaning for this particular rifle.

 

[wind gypsy]

Got the Hornady gear out and the bullet did not enter the lands anywhere near COAL of a factory round. hmmm. Tried several more times. Being a learner and having had some teething problems when I did this with the Swede and the ARC, I chambered a factory round to see what resistance I was getting. Was getting some resistance - see image below with the projectile getting damaged.

I think i get the jist of it but your wording is not very clear. In the bolded out and i believe you're saying you hit resistance from the carbon ring well before bullet was pressed into the lands?

Sounds like what people say happens with carbon rings.. What are the details on the rifle?

 

[dombo3]

Correct.

 

[dombo3]

Tikka action. Custom 25” Bartlein barrel.

 

[MT762]

Some cartridges and throats are really forgiving of never cleaning...some are not. Suppressors make the situation worse.

I've def shot thousands of 175gr SMKs through 308s and never cleaned them apart from a wet patch/cleaning the lugs. And was also taught at various schools: don't clean your bore. But my 6 creed with a suppressor will lock the bolt/blow primers after a few hundred rounds if I don't scrub it.

It's possible that if you are running a gun pretty hard that throat erosion (high round days with a hot barrel) will basically cancel out all carbon that was building up. The carbon builds up...but the throat keeps moving so the gun's behavior doesn't change.

Anyway...I am no longer sure. Except that I don't have to service my 308s nearly as much as I have to service my 6 creed.

 

[Dave Thomas]

Keep it clean. You'll have to decide how often it will need cleaning.