Switching to moly

[Waskawood]

I have decided to try moly in a newly chambered 17 TCM. The barrel has been shot with naked bullets. Do I need to clean it down to bare metal before using moly? TIA..............

 

[jonbearman]

I would clean it good for sure. Then you can monitor it for any copper showing up after firing.

 

[WillyTP]

This from the Berger Q&A section, hope it helps.

Berger Bullets Question & Answers


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How do I clean my rifle when using Moly Coated bullets?

The best procedure for cleaning when using Moly coated bullets is as follows:

1. Push one wet patch with Kroil Oil through the barrel.
2. Repeat Step 1.
3. Push one dry patch through the barrel.
4. Repeat Step 3.
5. Push one wet patch with Butch's Bore Shine through the barrel.
6. Repeat Step 5.
7. Let soak for five to ten minutes.
8. Push one dry patch through the barrel.
9. Repeat Step 8.
10. Short stroke one patch with USP Bore Paste through the barrel.
11. Push one patch wet with Kroil Oil through the barrel.
12. Repeat Step 11 twice.
13. Push one dry patch through the barrel.
14. Repeat Step 13 three times.
15. Use bore scope or visually check muzzle to insure barrel is free from copper fouling.
16. If inspection shows copper fouling still in barrel, repeat Steps 10 through 14.
17. If rifle is to be placed in storage, push one patch wet with a good grade of gun oil through the barrel.


How do I break in a barrel with Moly Coated bullets?

The procedure that Walt has found to be the best is as follows:

For a new barrel:

1. Fire one shot using a moly bullet then clean using moly cleaning procedure
2. Repeat Step 1 five times
3. Fire three shots using moly bullets then clean using moly cleaning procedure
4. Repeat Step 3 five times.

For a broken-in barrel:

1. Thoroughly clean barrel
2. Fire ten shots moly then clean using moly cleaning procedure

Your barrel will now be broken in.

 

[searcher]

I'd clean it really well, working to get as much of the carbon and copper out as possible. You will find that the cleaner your bore is prior to using moly, the less copper buildup you will have as a result once you start running the moly bullets. I also run a swab of moly paste back and forth, then polish off with clean patches before running my first moly bullets through the bore. That seems to minimize the initial coppering prior to a good layer of moly being laid down by the bullets. Works well for me. Borescoping can be a huge help to knowing how far to go when cleaning with a particular barrel - and when to stop short of removing all your moly if there are no signs of copper buildup.

 

[ericbc7]

I use boretech eliminator which seems to work well on moly, but +1 on general cleaning.

 

[Waskawood]

Thank you gentlemen. I appreciate the advice. I will scrub it up and start fire forming. This started life as a 17 VHA but when 22 TCM brass came available the fact that it has a 223 bolt face intrigued me. I put a 40 degree shoulder on it and necked it down to 17 caliber. The gunsmith test fired it with 12 gr. of 1680 so we will work up from there. Max capacity of the case is about 14 gr.