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View Full Version : Measuring grooves in original Maynard 2nd model



us1863
09-27-2008, 08:17 PM
Would like to get the grooves in an original 2nd model Maynard measured. It shoots a .515 Rapine round OK but looking to improove performance with a custom made round. Looking for someone going to the fall nationals who has a set of 3 fingered mics to measure the grooves in the barrel for a small fee.

RaiderANV
09-27-2008, 08:36 PM
Bring yer toy by Lodgewood and we'll gauge it fer FREE :shock:

We'll even have the correct mold/bullet fer ya 8)

us1863
09-27-2008, 09:25 PM
The Maynard shoots a .515 round OK but figured knowing the actual barrel diameter could only help. The Lyman 575213 I got from eBay didn't work out so still looking for a Lyman 580213 mold. Sent Lodgewood an email. Hopefully they have one.

Lou Lou Lou
09-28-2008, 10:11 AM
Tom
Push an oversized round through it from the breech. I have .517 and .518 rounds

us1863
09-28-2008, 11:07 AM
Thanks Lou,

Tried that method. Works OK to get an impression of the lands and grooves but accuratly measuring the 3 off-set grooves is still a problem. Now if they only had 4 lands and grooves a standard pair of mics would work.

Did you know crime investigators use a similar method? The paste dentists use to take an impression of your teeth is used to get an impression of the lands and grooves in a firearm. With this method they can match the marks on the bullet recovered from a crime to a firearm, even if the barrel has had a screwdriver shoved down the barrel after a crime was committed to change the marks left on the round. Just a little bit of useless trivia.

FlinchJerk
09-30-2008, 09:56 AM
10th Mass Type.....the magic specialized micrometer is named a V anvil micrometer. Google it on the internet and eBay to see what they are like. They are made in various sizes and mostly are used for precision measurement of 3-flute drill bits and milling cutters. The bullet-measuring V anvil micrometer has a range of .10 to .90 (or so). So push an oversize lead ball through the bore, making sure it completely fills the barrel grooves (no light showing as you look down the bore in the slugging process) to ensure a true profile of the barrel groove depth.

I will bring mine to Winchester this weekend. Where is the 10th Mass. camp?

There was a discussion about this device on the BB a few years ago, but the exact name of the tool didn't make then make it into the thread. My thanks go to the proprietor of AndyLand who pulled out a vintage Sterret catalog in his archives a while back to sleuth out the proper nomenclature.

Armed with the name, it was easy to find them on the internet. New, they can run as much as $500, used, around $150.....There are also V anvils to measure 5 grooves.

Yours in the hobby...
Dean Nelson
1st MD Infantry, CSA, N-SSA