IMPORTANT: Change to Berrys .38 COL Data

[Ben_Snow]

Started a post a few weeks ago on proper COL for Berry's Plated Bullets. In the thread it was noted that conflicting data existed between the COL chart located in the FAQ section of the Berry website, and COL data for similar published plated bullet profiles.

I just checked the Berry's website today, the COL Chart from the FAQ has been pulled. I also noticed each calibers COL data is now located with the specs for each bullet profile.

The COL for the .38 Plated FN has changed from the previous COL Chart. Here is the new data: (both are + .0010)

SAAMI MAX .357 Mag COL = 1.590
SAAMI MAD .38 Spl COL = 1.550

This is significant as it occured after the thread was posted and after emailing Berry's. Now sure if its a coincidence, or they are fans of the Firing Line.

Regardless, please DISREGARD my previously posted link to the Berry's COL chart. If you use Berry's plated bullets, please re-visit thier COL profiles to ensure there have been no changes to your favorite bullet choices.... thanks !

 

[Unclenick]

Ben,

Those number are just the SAAMI standard maximums that guarantee the will not stick out of the cylinder chambers of any revolver in those calibers, and should not be too short for the carriers in lever action rifles chambered for them. They are maximums, so there is no plus tolerance; only a minus tolerance. They are not unique to the bullets. I am guessing, from their shapes, you will find some cannot go that long.

The complete SAMMI standard dimensions are included in this document. Scroll down to page 44 (page 53 as Acrobat Reader counts them) for .357 Magnum, and page 47 (page 56 as Acrobat Reader counts them) for 38 Special. Both the cartridge and chamber drawing below it are on each page.

In that document, cartridge linear dimensions are maximums with a minus tolerance only, and chamber linear dimensions are minimums with a plus tolerance only. This is a standard engineering practice when one end of the tolerance range is considered critical. That end's number is given, and the tolerance only runs the other way from it (called a unilateral tolerance). In this case, those numbers are the cartridge not-to-exceed and chamber not-to-fall-below dimensions. Using those as critical limits prevents the possibility of making a cartridge that meets the standard that won't fit inside a chamber that meets the standard, nor a chamber that meets the standard that won't accommodate all cartridges that do.

For .38 Special, the COL range is:

1.275-1.550"

For .357 Magnum, the COL range is:

1.405-1.590"

The minimum numbers above are for bullet shapes that are standard (also listed in the SAAMI standard) and exist for some magazines and mechanisms that have minimum lengths. The minimums are so, for example, the carrier in a lever gun with a tubular magazine can't accept a whole cartridge and a portion of the next cartridge in the tubular magazine as wll, which would jam it.

Note that wadcutters are treated separately as Match loads in the .38 Special (page 48 or 57 in Acrobats page counter), and have a separate length specification, reflecting the fact only some guns will use it. The model 52 Smith&Wesson pistol, for example, was designed only for this cartridges and did not accommodate normal length cartridges. A revolver can use either one.

.38 Special Match wadcutter COL range is:

1.145-1.195"

 

[Ben_Snow]

Nick, Thats not my point

Berry's had their own COL chart located on the FAQ of their website. This has now been pulled, and they are now simply listing SAAMI specs on the tech data for each caliber and bullet profile. The change of course is not to that of SAAMI, but to the previous (and now defunct) chart Berry's had published.

The correction ( +.0010) is for those (such as myself) that had printed and was using the old Berry's COL chart.