Help! How to determine caliber?

[Potter4077]

I purchased a beautiful Jim Westberg rifle at a firearms show. The rifle was tagged as a 54cal. I don’t currently have a 54 cal so I ordered all the cleaning jigs, mop, ball puller, etc. I received them today and was going to clean the rifle and found that the rifle is smaller than a 54cal. It’s also smaller than my 50cal jigs, etc. Now I don’t know what the caliber is! There are no markings on the barrel or elsewhere. How do I figure out what caliber it is? Measure the muzzle opening? Then what?

[snapper]

Can you force a lead slug into the bore (and get it back out)?   Do you have a set of calibers?   

Fleener

[smylee grouch]

I would slug the barrel. Oil the barrel , drop a 6-8 inch brass rod down barrel, drive an over sized lead ball into muzzle WITH A WOOD MALLET,  upend the barrel and let  the rod slide down and knock the slug out, measure slug.

[mountainman70]

Maybe a .45. Nice gun, welcome to the Forum. Dave 

Time to invest in digital calipers to get a better read.

[A Scanlan]

Or maybe one of those little bore gauge.  $5 on Amazon.  What?  Jam a ball down the barrel!  I don't think so.

[DGB]

Hi,
Smylee gave good advise, I have done this many many times.Use a ball just slightly oversize if you have one.
DGB

[smylee grouch]

Or maybe one of those little bore gauge.  $5 on Amazon.  What?  Jam a ball down the barrel!  I don't think so.

s  Yes A Scanlan but the oiled bore and brass rod first and use a wood mallet to protect the muzzle. The whole process takes about 5 min. When you get the slug you can measure bore dia. - groove dia. and groove depth.    That is kind of standard operating procedure on the Bench Rest - Slug Gun - and Cross Stix line at many of the big shoots I have shot at and did Range Officer duty at.

[Potter4077]

Can you force a lead slug into the bore (and get it back out)?   Do you have a set of calibers?   

Fleener

I do have a set of digital calipers. I measured .447 in. I guess my answer is that it’s a 45cal rifle. If that’s correct, that was pretty simple. Thank you!

[Potter4077]

Maybe a .45. Nice gun, welcome to the Forum. Dave 

Time to invest in digital calipers to get a better read.

I do have a set of digital calipers. I measured .447 in. I guess my answer is that it’s a 45cal rifle. If that’s correct, that was pretty simple. Thank you!

[snapper]

I would think that Jim used a barrel that is not an odd cal.    When I mean odd something other then a .45, .50 .54 etc.

I would run with the .45 and now you just need to get balls and patches to see what the rifle like.

Fleener

[Flint62Smoothie]

These $10 Bore - Gauge & Cailber - key ring tools by Colt are cool!

[Daryl]

Advertised as .54, with the numbers reversed I expect.
Appears you measured the land to land, the smallest inside dia. at .447".
My own preference is this small bore, would be a .445" ball, but others might want use a .440".

[Potter4077]

I would think that Jim used a barrel that is not an odd cal.    When I mean odd something other then a .45, .50 .54 etc.

I would run with the .45 and now you just need to get balls and patches to see what the rifle like.

Fleener

I took it to TOTW (it’s only about a 45min drive for me). It’s a 45cal, so I bought all of the accessories, patches and balls. Now I just have to get to the range and shoot it. I’m a bit disappointed though, as I wanted a 54cal for deer hunting. I’d trade it if it wasn’t so beautiful. I’ll keep it and still use it for deer, I’ll just have to perfect my accuracy before hitting the woods this fall (as I do every year).

[Daryl]

Do a quick trip on the muzzle's crown. This will pay of in accuracy by allowing you to use a tighter ball and patch combination. Here is my .45's muzzle (& a .58) smoothed up by using 320 emery
cloth or wet/dry 320 paper and simply sticking your thumb into it on the muzzle and rotating your wrist. I shove a patch into the bore an inch to catch the 'grindings' which is easily pulled out with
tweezers or needlenose pliers. Every 10 to 15 seconds, stop and turn the barrel 90 degrees. Getting rid of the machine cut corners, stops the patch cutting by the lands when you load the rifle. With
a muzzle crown like this, I have easily loaded bore sized round balls with 10 ounce denim patching. That's currently .021"(compressed) patch in the last 10 ounce denim I bought.