Chambering same round more than once - Page 4
You are Unregistered, please register to use all of the features of FirearmsTalk.com!    
Firearm & Gun Forum - FireArmsTalk.com > Handguns > Concealed Carrying & Personal Protection >

Chambering same round more than once


Reply
 
LinkBack Thread Tools Display Modes
Old 02-22-2012, 04:04 AM   #31
Feedback Score: 0 reviews
 
canebrake's Avatar
 
Join Date: Jan 2009
Location: 150 miles NE of Sloppy Joe's Bar
Posts: 21,941
Liked 1461 Times on 819 Posts
Likes Given: 1290

Default

Quote:
Originally Posted by danf_fl View Post
The concern is not FTF, but over pressure.
Most SD rounds are already pushing the SAAMI standards. Setback creates more pressure. I've never had a gun blow up due to pressure, but I sure wouldn't want to chance it by rechambering the same rounds.

The .45ACP bullet is held in place by the casing. The ogvie of the bullet being pushed by the lands can and has created setback.
You nailed it dan!

This is a photo of a 460 Rowland with one chambering.

Chambering same round more than once - Concealed Carrying & Personal Protection

This is Georgia Arms "NEW" ammo with little-to-no crimp.

In the Rowland this increases the pressure to hot enough levels that Clark Custom Guns recommends to only chamber once and dispose of any unfired/chambered rounds.
__________________
http://i695.photobucket.com/albums/v...brake02jpg.jpg

http://i1060.photobucket.com/albums/...ps18cfbeae.jpg

Get her dirty, then clean her so she starts to respect you. When her trust is complete, she will serve you well for a lifetime!

"...if doves shot back, there wouldn't be a need for a bag limit."
- orangello
canebrake is offline  
 
Reply With Quote
Old 02-23-2012, 09:06 PM   #32
Feedback Score: 0 reviews
 
redteck215's Avatar
 
Join Date: Jan 2012
Posts: 27
Default

I replace all self defence ammo at least twice a year. I use standard hollow points from hornady the 200 grain. Now i shoot it all up bout twice a year not because im woried bout the rechamber thing but if im using it to stop a threat i want fresh ammo.
redteck215 is offline  
 
Reply With Quote
Old 02-24-2012, 12:48 AM   #33
I used to play keyboards, but now ...
FTF_MODERATOR.png
Feedback Score: 0 reviews
 
Balota's Avatar
 
Join Date: Dec 2011
Location: Glenpool, Oklahoma
Posts: 5,843
Liked 4717 Times on 2787 Posts
Likes Given: 3867

Default

OK, I ran the experiment with many chamberings. I wrote up a report that's too long to post, but maybe they'll let me submit it as an article. The short version is this: For the Hornady Critical Defense 9mm ammunition in an XDm 9mm Compact pistol, the total accumulated setback after 50 cycles was 0.008".

To put that in context, the longest round in the box was 1.097" and the shortest round was 1.074". So the setback after 50 cycles was about 1/3 of the variance in length for all the rounds in the box. Almost all of this setback occurred in the first 15 cycles. After that there was almost no change in length. I started with the cartridge whose length was right in the middle of the collection in the box (the median round for those mathematicians out there). After all the setback was taken, the round was still longer than two of the untouched rounds in the box.

Looks to me like setback is not a serious issue for my combination of firearm and ammunition. But it's also clear from Canebrake's photo that other ammo in other weapons may have very different results. Please don't use my results to draw conclusions about your weapon and ammo. If you have a concern about this, run the experiment yourself with your gear.

My intention is to use the chambered round as my first practice round to get an idea of my first round proficiency. The round I chamber after practice will be cycled at least once when I clean my gun after practice and perhaps 4 or 5 more times when I dry fire. But for my combination, after 6-7 chamberings I've only lost 0.003" and I'm not going to worry about that one.
__________________
Balota
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." 2nd Amendment to the Constitution of the United States
Practice does NOT make perfect. Practice makes permanent. Only perfect practice makes perfect.
Balota is offline  
 
Reply With Quote
Old 02-24-2012, 01:08 AM   #34
Feedback Score: 0 reviews
 
Join Date: Feb 2011
Location: West, by God, Funroe,Louisiana
Posts: 18,707
Liked 9217 Times on 5060 Posts
Likes Given: 74

Default

Good report Balota. Maybe you should write it up as a full article like you mentioned, it would be a good one.

Do you have other guns and ammo to diversify your findings?
trip286 is offline  
 
Reply With Quote
Old 02-24-2012, 01:35 AM   #35
I used to play keyboards, but now ...
FTF_MODERATOR.png
Feedback Score: 0 reviews
 
Balota's Avatar
 
Join Date: Dec 2011
Location: Glenpool, Oklahoma
Posts: 5,843
Liked 4717 Times on 2787 Posts
Likes Given: 3867

Default

Quote:
Originally Posted by trip286 View Post
Good report Balota. Maybe you should write it up as a full article like you mentioned, it would be a good one.

Do you have other guns and ammo to diversify your findings?
I went to the Articles page and clicked Submit Entry. Just got a button labelled Request Writer Status. Clicked that. Now waiting for an admin to get in touch. That was just last night and I'm sure they have plenty else to do. Managing folks like us is like herding cats !

My only other gun is a recently bought S&W 22A for cheap practice. Only shot that once for about 150 rounds before shooting my 9mm. It helped a lot.

My son has a Taurus PT92 9mm that I could probably use to see if the weapon makes much difference with the same ammo. He's also looking at the Corbon all copper round (DPX?). I could probably get him one box of that and test it in both weapons. Beyond that, I'd have to invest in several boxes of different ammo. I don't have a budget like the NIST, so that would probably just be a once in a while thing.
__________________
Balota
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." 2nd Amendment to the Constitution of the United States
Practice does NOT make perfect. Practice makes permanent. Only perfect practice makes perfect.
Balota is offline  
 
Reply With Quote
Old 02-24-2012, 08:23 AM   #36
Retired
FTF_SUPPORTER.png
Feedback Score: 0 reviews
 
danf_fl's Avatar
 
Join Date: Apr 2010
Location: LA (Lower Alabama),FL
Posts: 11,786
Liked 4167 Times on 2343 Posts
Likes Given: 1960

Default

Good report! Thanks.
Please keep us informed.
__________________
Amendment II:
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."

Life Member NRA
Life Member NAHC
Former President of the ECPT (Eifel Combat Pistol Team)
danf_fl is offline  
 
Reply With Quote
Old 02-25-2012, 09:29 PM   #37
I used to play keyboards, but now ...
FTF_MODERATOR.png
Feedback Score: 0 reviews
 
Balota's Avatar
 
Join Date: Dec 2011
Location: Glenpool, Oklahoma
Posts: 5,843
Liked 4717 Times on 2787 Posts
Likes Given: 3867

Default

Quote:
Originally Posted by Balota View Post
My intention is to use the chambered round as my first practice round to get an idea of my first round proficiency.
Just checked my first round proficiency ... Wish I could say I'm that good but for now I'll have to settle for that lucky!
firstround.jpg  
__________________
Balota
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." 2nd Amendment to the Constitution of the United States
Practice does NOT make perfect. Practice makes permanent. Only perfect practice makes perfect.
Balota is offline  
 
Reply With Quote
Reply

Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Firearms Forum Replies Last Post
Re-chambering for my Savage 110 divarty General Rifle Discussion 20 02-02-2012 12:20 AM
AK-74 Polish Tantal Problems chambering first round AK74 Auto & Semi-Auto Discussion 2 01-24-2012 05:16 AM
Chambering Round, Not Firing It PeteZaHut Ammunition & Reloading 3 04-05-2011 01:21 AM
Colt 1903 fires when chambering a round tmossberg Gunsmithing Forum 3 09-04-2010 10:28 PM
Browning fires while chambering round? Lizzard General Rifle Discussion 5 12-28-2008 01:32 AM