Hi fellas: This is a greenhorn question, I'm sure, but as they say, "there are no dumb questions"--in looking at a used rifle, how does one identify or what defines, throat erosion, and a worn out barrel? Can you tell with the naked eye? Are there any tools/instruments that would be helpful in doing this?

Any help/advice in this area would be greatly appreciated. Thanks!

Crusader---

A bore scope would tell you everything about it you can tell without shooting it, but they're expensive.

Look for the *difference* in sharpness, or crispness of the rifling immediately ahead of the throat as compared with further down the barrel.

If an inch or so ahead of the chamber looks dark or scaly (gator hide), or the rifling seems to be speckled looking and rounded, buy it for the all the parts *but* the barrel. It's a tomato stake.

I would like to have a bore scope a whole lot, but I have priced them. I use the el Cheapo method for monitoring throat erosion. It would tell me very little about how much to pay for a rifle.

I have a bullet seating depth gauge from Stoney Point. Its usual application is to determine how far out to seat a bullet so as to just contact the lands of the rifling or to seat a bullet a certain distance off the lands of the rifling.

I have periodically monitored a 30-06 caliber rifle over perhaps 1000 shots, and the lands start 0.050" farther down the barrel than they used to. I have noticed no change in accuracy with factory ammunition, which I assume has always been seated to the same depth and which now gets a 0.050" longer runnning start before the bullet hits the rifling.

H. C.

[ 04-28-2003, 16:24: Message edited by: HenryC470 ]

The high power crowd which I am a part of mostly use the stoney point gauge. In the begining to establish the seating length of the 80 grain long range bullets in a new barrel and then to monitor it as the throat "grows". 10 thousandths per 1000 rounds seems to be an average in the .223. The thing is that the growth of the throat does not seem to be the decideding factor as to when a barrel is "gone". The only way to really know is when the groups open up appreciably or you start getting uncalled fliers at 600 yards. Even at that point most barrels still shoot well enough at 200 yards to stay competitive but usually end up as the practice gun for 200 yd rapid fire and offhand. As Mr. Belk mentioned the dry lake bed look of the throat is where I think the problem is, at some point a chip or flake of steel gets a 2700 FPS ride down your barrel and goodbye. If only more hunters shot out barrels there would be a lot less misses and wounded game, a 308 barrel can go 5-6000 rounds.

I have a bore scope and I dread looking. The very sight of a scaly cracked throat makes me think of rebarreling. In actuality if it still shoots well who cares! Ihave one .50BMG barrel retired from the .50BMG matches that looks like Mt Vesuvius inside after 1200 rds! It will still shoot .5MOA groups!-Rob

I used to be able to see erosion easily but my eyes are old now and don't focus as well. I can't really hold my face to the stock that well to see in with my progressive glasses. But I can see well enough to get suspicious if the bore is clean.

I do have a Wally Siebert bore scope however. This is a $20 item thats perfect for looking into bores for throat erosion. It's a piece of brass tubing the diameter of a standard .7" bolt and about the same length with a lense in just one end. It gives the best magnified view of a throat you could imagine. It is easy to use without glasses but my right eye correction is only 1.5 so I don't know about everyone. It only really works well with bolt actions. It can be held to work on a SS but not of course on auto's etc.

I got it from Sinclair. They don't carry them any more.

This is worth some kind of an effort to get someone to make another lot of these.

I brought it with me in my pocket when I met my new gunsmith last year. His eyes bulged out and he did not want to let go of it. He said he has a borescope. You know the kind that examines a small area at a time way inside the bore. I would like to have one of those but I don't.

I would not sell this borescope at any price. Thats how cool it is when your in a gunshop or show.