Parker Gun Collectors Association Forums  

Go Back   Parker Gun Collectors Association Forums Non-Parker Specific & General Discussions Shotgun Shell Reloading

Notices

Reply
 
Thread Tools Display Modes
Cheddite Primer pressure spikes
Unread 04-06-2022, 07:37 PM   #1
Member
J.B. Books
PGCA Member
 
Pete Lester's Avatar

Member Info
 
Join Date: Jun 2009
Posts: 2,865
Thanks: 1,643
Thanked 4,802 Times in 1,369 Posts

Default Cheddite Primer pressure spikes

From trapshooters.com. A poster had some loads tested and this stood out.

The first load with a Win 209 and 15.7 gr of 20/28 is listed on the Alliant Reloading Guide as being 1200 fps and 9370 psi.

The second load with a Win 209 and 16.7 gr of 20/28 is listed on the Alliant Reloading Guide as being 1250 fps and 10,490 psi.

Hull: Win AA 20 ga
Wad: CB1078-20
Shot: 7/8 oz
Primer: Cheddite
Powder: 15.7 gr 20/28

Ave pressure: 12,685 psi
Ave velocity: 1306 fps


Same as above except 16.7 gr 20/28

Ave pressure: 14,022 psi
Ave velocity: 1354 fps


https://www.trapshooters.com/threads...esults.918249/
__________________
Progress is the mortal enemy of the Outdoorsman.
Pete Lester is offline   Reply With Quote
Unread 04-06-2022, 08:04 PM   #2
Member
Aaron Beck
PGCA Member

Member Info
 
Join Date: Jan 2021
Posts: 297
Thanks: 52
Thanked 197 Times in 120 Posts

Default

Cheddite makes several flavors of primer. I am pretty sure we can only get the 2000 kind, but wonder if rst has access to the 1000. It seems like this might result in lower pressures but im not an engineer.
Aaron Beck is offline   Reply With Quote
The Following User Says Thank You to Aaron Beck For Your Post:
Unread 04-07-2022, 10:21 AM   #3
Member
Mike of the Mountain
PGCA Lifetime
Member

Member Info
 
Join Date: Feb 2014
Posts: 4,760
Thanks: 15,539
Thanked 8,864 Times in 2,674 Posts

Default

Quote:
Originally Posted by Aaron Beck View Post
Cheddite makes several flavors of primer. I am pretty sure we can only get the 2000 kind, but wonder if rst has access to the 1000. It seems like this might result in lower pressures but im not an engineer.
RST buys primed hulls. I can't answer whether they can specify which primer or if they only manufacture shells with one primer (2000 vs 1000). My guess would be whatever primed hulls Cheddite produces they use one primer to keep costs down.
Mike Koneski is offline   Reply With Quote
Visit Mike Koneski's homepage!
Unread 04-06-2022, 08:14 PM   #4
Member
Andy
PGCA Member

Member Info
 
Join Date: Dec 2019
Posts: 1,850
Thanks: 257
Thanked 2,461 Times in 969 Posts

Default

Well this is fraught with all kinds of scientific holes. Did he measure the powder loads with a scale rather than just trust the bushing? I spent a lot of time measuring powder throws with an RCBS digital scale, and sure enough I varied quite a bit as much as I tried to be consistent. Chamber length compared to the manual? Hull? Temperature? How many times have we run a chronograph on our loads and we "average them" because they vary so damn much. I think we need a heck of a lot more detail before we say Cheddite cause pressure spikes. That's just MY opinion and I'm pretty new at this but I'll say we need more evidence.
__________________
Nothing ruins your Friday like finding out it's only Tuesday
Andrew Sacco is offline   Reply With Quote
The Following 4 Users Say Thank You to Andrew Sacco For Your Post:
Unread 04-07-2022, 04:26 AM   #5
Member
J.B. Books
PGCA Member
 
Pete Lester's Avatar

Member Info
 
Join Date: Jun 2009
Posts: 2,865
Thanks: 1,643
Thanked 4,802 Times in 1,369 Posts

Default

Quote:
Originally Posted by Andrew Sacco View Post
Well this is fraught with all kinds of scientific holes. Did he measure the powder loads with a scale rather than just trust the bushing? I spent a lot of time measuring powder throws with an RCBS digital scale, and sure enough I varied quite a bit as much as I tried to be consistent. Chamber length compared to the manual? Hull? Temperature? How many times have we run a chronograph on our loads and we "average them" because they vary so damn much. I think we need a heck of a lot more detail before we say Cheddite cause pressure spikes. That's just MY opinion and I'm pretty new at this but I'll say we need more evidence.
What makes the test results of reloads sent for testing by a member of Trapshooters.com more suspect then reloads tested by the members of the PGCA?
__________________
Progress is the mortal enemy of the Outdoorsman.
Pete Lester is offline   Reply With Quote
Unread 04-07-2022, 06:43 AM   #6
Member
Andy
PGCA Member

Member Info
 
Join Date: Dec 2019
Posts: 1,850
Thanks: 257
Thanked 2,461 Times in 969 Posts

Default

It doesn’t. The list of things that affect pressure are the hull (how many reloads), powder throw, the crimp and we can go on. My point is how do you know it’s the primer that made the pressure higher or a combination of things?
__________________
Nothing ruins your Friday like finding out it's only Tuesday
Andrew Sacco is offline   Reply With Quote
Unread 04-07-2022, 07:40 AM   #7
Member
Cold Spring
PGCA Member

Member Info
 
Join Date: Jun 2009
Posts: 1,901
Thanks: 3,338
Thanked 6,309 Times in 1,218 Posts

Default

On that Trapshooter thread; many replies but so far the OP has been reticent to reveal the lab or source that did the pressure testing. ?????
Frank Srebro is offline   Reply With Quote
The Following 2 Users Say Thank You to Frank Srebro For Your Post:
Unread 04-07-2022, 09:04 AM   #8
Member
J.B. Books
PGCA Member
 
Pete Lester's Avatar

Member Info
 
Join Date: Jun 2009
Posts: 2,865
Thanks: 1,643
Thanked 4,802 Times in 1,369 Posts

Default

I will continue to watch the thread and hope the OP provides that info. I doubt he is making up a story. One way or the other it would be good to know the facts.

Quote:
Originally Posted by Frank Srebro View Post
On that Trapshooter thread; many replies but so far the OP has been reticent to reveal the lab or source that did the pressure testing. ?????
__________________
Progress is the mortal enemy of the Outdoorsman.
Pete Lester is offline   Reply With Quote
The Following User Says Thank You to Pete Lester For Your Post:
Unread 04-07-2022, 09:55 AM   #9
Member
Pa SxS
Research Chairman
PGCA Lifetime
Member
 
Chuck Bishop's Avatar

Member Info
 
Join Date: Nov 2008
Posts: 2,867
Thanks: 1,204
Thanked 4,960 Times in 1,418 Posts

Default

I asked Alliant a couple of years ago about primer swapping, specifically swapping primers in 20 and 28 gauge guns. I wasn't concerned about 12 ga. because my pressures were in the 6k to 7k range. I asked them if using their published components, would it be safe to substitute only the primer? They didn't have the specific primer I wanted to use but they said they tested all the popular primers in their published loads and the highest pressure spike they observed was 2,500 psi. SAAMI service pressures are 12,000 psi for 20ga. and 12,500 psi for 28ga.

So, if you want to substitute a primer into their published recipe, add 2,500 psi to their data and if it's below SAAMI limits, you can substitute. They advised me not to do it in 28 ga.
Chuck Bishop is offline   Reply With Quote
The Following 2 Users Say Thank You to Chuck Bishop For Your Post:
Unread 04-07-2022, 10:05 AM   #10
Member
J.B. Books
PGCA Member
 
Pete Lester's Avatar

Member Info
 
Join Date: Jun 2009
Posts: 2,865
Thanks: 1,643
Thanked 4,802 Times in 1,369 Posts

Default

The poster on Trapshooters.com posted the following this morning.

"The testing was done at precision reloading. I didnít post the pictures of the actual test results because I never posted pictures and need to figure out how. Just havenít had time yet. Once I figure it out I will post on Georges thread once he creates it."
__________________
Progress is the mortal enemy of the Outdoorsman.
Pete Lester is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 01:11 AM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright © 1998 - 2024, Parkerguns.org
Copyright © 2004 Design par Megatekno
- 2008 style update 3.7 avec l'autorisation de son auteur par Stradfred.