The Bore of My Sub 2k Barrel to Small Should I be Worried?

[jpaullette]

After a pleasent day at the range I stopped by my local gun store to buy a boresnake to make cleaning less of a hassel. They did not have any boresnakes in 9mm so I bought the .357 being only .001 of a inch difference. So I go home break down the Sub and begin cleaning the gun. I began to run the snake through the barrel and I pulled but it wouldnt budge. I tried my hardest to pull it through without breaking it but it wouldnt yeild so I went back to the gun store and I told the man who sold it to me my problem. I gave him the boresnake and he ran it through the 9mm sub 2000 they had in stock and it went through just fine. This kinda worried me but the employee let me switch it out for a .30 bore snake and it fit just right for my gun. Should I be worried that the bore of the barrel is smaller than normal? Would this cause any problems while firing it that may damage the rifle? Any help or advice would be great.

[plinkertoo]

If it was truly undersized I don't think it would have fired the 9mm ammo you used. .30 cal is more like a 7.62 size, and if your sub had a 7.62 bore it wouldnt have fed much less fired the round. Brand new bore snakes are very hard to pull through a barrel. I have several in different calibers and will vouch for this. It is also possible on occasion to catch the end of the nylon patch material on one side of the chamber and make it feel like it is stuck. I wasn't there so I'm not saying it didn't happen to you. I am certain they only make the Sub in 9mm and .40. So that barrel cannot be undersized.

[corsairgunner]

i think when i bought my boresnake the 357 and 9 were the same size.

[jpaullette]

Brand new bore snakes are very hard to pull through a barrel. I have several in different calibers and will vouch for this. It is also possible on occasion to catch the end of the nylon pautch material on one side of the chamber and make it feel like it is stuck. I wasn't there so I'm not saying it didn't happen to you. I am certain they only make the Sub in 9mm and .40. So that barrel cannot be undersized.

Their where no obstructions to the barrel at the time and it wasnt a matter of trying hard enough. I pulled on it continuesly on both ends of the barrel but it wouldnt go in but a half an inch and took just about much as force to pull that half inch back out. Also when I have been cleaning with a brush I cannot use the .357 bore brush because it wont go in about a half an inch. as I said earlier when they ran the same boresnake through their 9mm sub 2k it went through perfectly so Its obviosly not undersized by a great deal or else it would be inoprable as you said. I have fired 500+ rounds without a failure to fire but the bore is smaller by some margin maybe just a couple thousandth of an inch difference somthing that is still big enough to let the bullet pass through but still smaller than the standard. I do not know how big the bore is currently but once the christmas holiday is over im going to borrow a friends dial caliber which can measure the bore within .001 of an inch so when I get my results I will be sure to post them and see what you all make of it.

for now ignore the possibility that its the standard size. If the bore diameter is smaller than standard but still can fire properly then will that cause any malfunctions and or damage to the gun?

[corsairgunner]

i would think the smaller size would cause more back pressure. but after 500 rounds and no failure i dont think its an issue.

[jpaullette]

k thanks for the advice

[Stogies]

I was pretty surprised the first time I used a new boresnake, I had to really pull with all my (measly) might to get the thing thru. It's gotta be a break in issue on the boresnake. Maybe the guy at the store was really all muscled up underneath his shirt and just made it LOOK easy?

[kevinsmith5]

If you're truly worried you can slug the bore.

[meanmrmustard]

If it was truly undersized I don't think it would have fired the 9mm ammo you used. .30 cal is more like a 7.62 size, and if your sub had a 7.62 bore it wouldnt have fed much less fired the round. Brand new bore snakes are very hard to pull through a barrel. I have several in different calibers and will vouch for this. It is also possible on occasion to catch the end of the nylon patch material on one side of the chamber and make it feel like it is stuck. I wasn't there so I'm not saying it didn't happen to you. I am certain they only make the Sub in 9mm and .40. So that barrel cannot be undersized.

7.62 IS .30 cal, and a new bore snake is VERY difficult to pull through first time. Doubly true when using a .22 snake in a 556 AR, as it catches the deep rifling and barrel extension. As Plinker has stated, it is for sure not undersized, so there is another issue afoot.

[the_mad_rshn]

Just slug the bore of your gun. It is very simple. Here are the instructions that used many times to do just that: Mosin Nagant Rifle Bore Slugging Tutorial

Cheers,
Mad