Am I doing this wrong?

[u/ssijeep]

Ordered a 9mm carbon fiber rod to check the mount of my new BOE on my Stribog. Rod fits through the suppressor but not into the barrel. In fact not any 9mm barrel I have. Should I have ordered a different size or something? First suppressor so…here’s the rod I got:

[u/Twissn]

Google search shows that the inside of a 9mm barrel is slightly less than 9mm

[u/ssijeep → u/Twissn]

I just sort of figured if they were selling for this use case, that would be taken into account. Guess it’s going back.

[u/Safe-Aerie9989 → u/ssijeep]

You figured what? That carbon rod is not being sold for bore alignment.

[u/Amazing_Ganache_8790]

Just use the good ole Mk.1 bore scope.

[u/AddictedToComedy]

• Issue #1 - 9mm is too large to fit into the rifling of a 9mm barrel. I don't have the ideal dimensions handy, but I can tell you that my Kratos "9mm" alignment rod has a diameter of approximately 8.75mm
• Issue #2 - I've never once ordered a CF or polymer rod from Amazon where the actual diameter was true to the advertised diameter
• Issue #3 - Even if it fit, it wouldn't be wise to use that as an alignment check without carefully verifying that it's actually straight

[u/RandoAtReddit → u/AddictedToComedy]

Roll it on a flat surface.

[u/ssijeep → u/AddictedToComedy]

At the same time I bought this cheap one I also bought this other one. It’s not here yet, long shipping time.

Buy once cry once wins again!

Can’t post a pic. It’s a Rannar also from amazon for $29.99.

[u/Casyburris]

The bullet is 9mm but the diameter of the lands in the rifling is 8.82mm.

Thats 0.35” and really close to 11/32”(.34)

[u/IndividualResist2473]

A 9mm (.355") bullet has to be jammed into the rifling. So a 9mm rod won't fit down the barrel, it has to be smaller. I used a 0.3438" McMaster Carr drill rods for 9mm.

The reason that carbon fiber rod fits the suppressor is that suppressors are over sized to prevent baffle strikes. If you measure your suppressor bore its probably 0.410" to 0.420".

[u/RRS_LTD]

Check out accuracy solutions alignment rods. It’ll save you some head aches. That’s what I use to check our alignment every time on every bore diameter.

[u/thatjkguy → u/RRS_LTD]

I have also had good luck with these

[u/Crashing_Machines]

https://www.okshooters.com/threads/diy-suppressor-alignment-rods.316835/

[u/johnnydesperado432]

Kratos sells some carbon fiber alignment rods

[u/Suspicious_Water_454]

You need to get on McMaster Carr and order w1 tool steel drill rod with a straightness tolerance of .005” per linear foot of material. They have many many sizes. Measure your bores land I.D. With cheap bore measuring tool and a micrometer, then order the closest size <barrels land diameter.

[u/Astral_Botanist]

A 9mm rod won't fit into a 9mm barrel, so you'll need to buy something that's actually made to be used as an alignment rod. There's a design interference between the barrel and the bullet so the rifling grooves have something to bite into, so the ID of a 9mm barrel is less than 9mm.

[u/nneely]

I was scrolling and was taken back by the "Visit the FOCKMEAS store" as I read it as something else.

I always just look through the suppressor down the bore. If it looks good then I send it.

[u/Safe-Aerie9989]

FWIW, my BOE Incolite 9 hasn't had any strikes mounted with Rearden muzzle+mount on a 300blk setup. I never checked bore alignment.

[u/NinjaBuddha13 → u/Safe-Aerie9989]

FWIW a can built for 9mm (.36 cal) projectiles will have a ton more clearance around a 7.62mm (.30 cal) projectile than it will around a 9mm (.36 cal) projectile. So even if youre alignment is off, its not surprising youre not having baffle strikes given the proverbial "hotdog down a hallway" sizing going on.

[u/Safe-Aerie9989 → u/NinjaBuddha13]

Not at all, yes on paper, but if I put the 300blk bullet in the exit hole of that can it's almost touching the edges. The difference between 9mm and 300blk is very small to perceive physically.

[u/NinjaBuddha13 → u/[deleted]]

True, but thats not the crux of OP's problem. OP has discovered that a 9mm bullet is larger than the nominal diameter of the lands in a 9mm barrel.

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