Smith & Wesson Forum

Advertise With Us Search
Go Back   Smith & Wesson Forum > Smith & Wesson Revolvers > S&W Antiques

Notices

S&W Antiques S&W Lever Action Pistols, Tip-Up Revolvers, ALL Top-Break Revolvers, and ALL Single Shots


Reply
 
Thread Tools Display Modes
  #1  
Old 01-24-2012, 10:19 AM
LRP's Avatar
LRP LRP is offline
Member
range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge  
Join Date: Jan 2012
Posts: 6
Likes: 0
Liked 0 Times in 0 Posts
Default range lead units of pressure gauge

i,ve been reading up on c.u.p and l.u.p.
the lead units of pressure is used for lower pressure.
it would be nice if somebody would develop a range
system to check the pressure in our antique guns.
i can see useing a special pair of adjustable pliers for diff size brass that would put a little dimple in the brass.
u would stick a thin disc or strip of lead in the brass dimple,
load and fire. u would use a lee type of microscope that they use for the lead hardness tesster. it has a calbrated scale
that would tell u how much wider it got . u would then look at a chart which tell u the pressure. i know, i get these brain farts
ever so often. if i was rich, i would buy the OEHLER chrono
with the pressure transducer.
cheers
Reply With Quote
  #2  
Old 01-25-2012, 08:51 PM
DWalt's Avatar
DWalt DWalt is offline
Member
range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge  
Join Date: Dec 2009
Location: South Texas & San Antonio
Posts: 33,647
Likes: 244
Liked 29,162 Times in 14,100 Posts
Default

The use of LUP and CUP for chamber pressure measurement is a holdover from the days when electronics did not exist. At best, they are imprecise and do not actually measure peak chamber pressure, but rather are simply analogous the area under the pressure-time curve. While the CUP and LUP methods are still covered under SAAMI pressure measurement standards, you are absolutely wasting your time in even considering them for home use, for any of many very good reasons. Forget it. The idea you propose could not and would not work.

Virtually all industry and government chamber pressure testing worldwide now uses some type of system based upon a very rapid response piezoelectric pressure gauge that allows an actual pressure vs. time trace to be captured and is capable of very precisely determining the actual peak chamber pressure. These systems are quite expensive, complicated, and are therefore wholly unsuitable for use by individuals. Piezo-based systems (and there are several types) are vastly superior to the old CUP and LUP methods for those users that actually need this data every day.

For both of the previous methods, a specially-designed or modified dedicated pressure gun is required. Not likely that many could afford those also, or would even be able to use one.

There is a system sold for use by individual reloaders that is reported to be almost as good as a piezo gauge. It uses an external strain gauge which is cemented to the exterior of the barrel of an ordinary rifle or shotgun. It is a bit costly, but is within the financial reach of many. Having not used it myself, I can offer no opinion, but there's quite a bit of information on the internet about it. If you want to use such a strain gauge system for pistol ammunition, you would necessarily have to use something like a single shot Thompson Center handgun caliber barrel chambered for the caliber you desire. YOU CANNOT USE YOUR ANTIQUE HANDGUNS FOR THIS PURPOSE!!!

Last edited by DWalt; 01-25-2012 at 09:07 PM.
Reply With Quote
  #3  
Old 01-25-2012, 09:27 PM
LRP's Avatar
LRP LRP is offline
Member
range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge range lead units of pressure gauge  
Join Date: Jan 2012
Posts: 6
Likes: 0
Liked 0 Times in 0 Posts
Default

well DWalt; you are correct except the part about wasteing my
time. the avarage reloader has nothing but a chrono to
go by to load for these antiques. the lyman reloader 46th
edition has the vel and pressure for the 38 spl. that is going to be my test bed. i have built 4 airoplanes and logged 5000 hrs
on them and no problems. now i know how the wright bros
felt. that thig will not fly. LOL. it,s not going to cost much to try.
never say die.
cheers
Reply With Quote
Reply

Tags
chamber pressure, thompson


Posting Rules
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
14-5 full underlug serial range for first 2000 units? S&W_aussie S&W Revolvers: 1980 to the Present 2 02-26-2012 05:23 AM
I can get free range lead Avery11 Reloading 8 03-21-2011 01:29 PM
Lead roundnose v. Lead semiwadcutter for range ammo volgunner Ammo 12 03-16-2011 07:17 PM
salvaging range lead... Leeroy151 The Lounge 12 07-27-2009 11:19 PM
Reclaiming lead from indoor range? MrPhil Reloading 8 03-21-2009 06:17 PM

Powered by vBadvanced CMPS v3.2.3
smith-wessonforum.com tested by Norton Internet Security smith-wessonforum.com tested by McAfee Internet Security

All times are GMT -4. The time now is 06:52 PM.


Smith-WessonForum.com is not affiliated with Smith & Wesson Holding Corporation (NASDAQ Global Select: SWHC)