ShotGunWorld Shotguns

It is currently Tue Jan 19, 2021 1:55 pm

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 30 posts ]  Go to page Previous  1, 2
Author Message
 Post subject: Re: A300 gas system maintenance
PostPosted: Mon Dec 21, 2020 7:22 am 
Diamond Grade

Joined: Thu Jul 15, 2004 1:56 pm
Posts: 1315
It is good advice to buy ammo that works. However in today's
market, I take what I can find, and most times that is nothing.
I have enough components to load about 6 months, and maybe
ammo sales will normalize by then.




Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Tue Dec 22, 2020 1:25 pm 
Diamond Grade

Joined: Thu Jul 15, 2004 1:56 pm
Posts: 1315
Solved, the problem is solved. The cause of
the weak or no ejection was fast powder in the
Winchester Universal.

To review what the Universal 3 dram contained:
___ 15.3 grains of some fast powder
___ 1 1/16 ounce of shot
___ muzzle velocity of this load - 1160 fps
___ this load did not cycle the gun.
These were barely 2 3/4 dram loads although
sold as 3 dram loads.

So I loaded up Universal cases with some powder,
yea I put together this load which is supposed
to be a 2 3/4 dram load and here are the specs.
___ 17.3 grains of Clay Dot
___ 1 1/8 ounce of shot
___ muzzle velocity was 1158 fps (measured on chrono)
___ this load threw the shells 3 feet and cycled the gun.

There is the story, 2 more grains of powder which is
obviously slower than the original, and the gun gives
same velocity as the 15.3 grains in the factory load,
and it works. This is actually a 2 3/4 dram load from
the velocity, so the gun cycles 2 3/4 dram Winchester
Universal shells if they have enough powder to keep
the pressure curve up far enough down the barrel to
the gas port.
---------------------------------------------
I also loaded up some of these Universal cases
with my 7/8 ounce load that I had shown with
the STS cases. Review here:

STS cases:
7/8 ounce STS I chronoed at 1285 avg and they threw
the shell 3 feet.

Winchester Universal:
7/8 ounce chronoed at 1343 fps and threw the shells
3 or 4 feet.

These shells used a different wad, than the STS cases,
but I did not change the powder or shot load, which
was somewhere around 18 grains of Clay Dot, and
7/8 ounce of shot.
-----------------------------------------
I have a new respect for Universal shells after this.
I thought before that the steel base was what caused
the intermittent cycling. Now I am pretty sure it
is fast burning powder that gives cycling problems
in gas autos. You would expect no problem from them
in doubles, pumps, or inertia autos. You might
not even expect trouble from them in a gun with the
ARGO system like Remington V3 which has the gas ports
right at the case mouth.

When the gas ports are located far from the chamber,
then fast powders that get their velocity early on
from higher chamber pressures then pressure reduces
faster as the load travels down the barrel, you end
up with lower pressure at the gas ports than you get
with slower powders which give lower maximum pressure
but hold their pressure longer as the load travels
down the barrel.
------------------------------------
All this last shooting was done with the exhaust
spring removed from the A300 and a steel cylinder
replacing the spring.


Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Tue Dec 22, 2020 3:42 pm 
*Proud to be a*
*Proud to be a*
User avatar

Joined: Sun Jul 27, 2003 3:37 pm
Posts: 19474
Hold on a second. I'm not convinced that the problem was due to the "fast powder" that was in the Win Universal shells. Based on what you told us, the problem may have simply been due to inadequate pressure at the gas ports due to a couple of things.

The first thing is inadequate amount of powder. The second thing is inadequate amount of shot. Those two things combined resulted in inadequate gas pressure at the gas ports.

The way to test this is to cut open a couple of Win Universal shells and take enough powder to weigh the same as your comparison reload of 17.3 grains. Then add enough shot to make it 1 1/8 ounce weight as in your comparison reload.

Now, at that point you'll have a load of 17.3 grains of whatever powder they used under a shot weight of 1 1/8 ounce of shot. These two increases in my opinion will likely result in successful operation of your gun... proving that the problem wasn't really the burn rate of the OEM powder but simply not enough powder and not enough shot weight to produce adequate pressure to cycle the gun.

P.S. There are no guarantees from me that the load I suggested is a SAFE load since we don't know for sure what type powder was used in the OEM shells. So it's up to you to try this or not at your own risk. You might try splitting the difference on the powder (say about 16.3 grains of OEM powder) pushing the 1 1/8 ounce load. I'll bet that will work, but again, it's up to you to decide whether you want to try it.

_________________
Please post For Sale items in the proper Classified section.

Semi-Auto Classifieds is ONLY for Complete Semi-Auto shotguns.
Over/Under Classifieds is ONLY for Complete O/U shotguns.
Items other than a complete shotgun go in OTHER Classifieds.


Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Tue Dec 22, 2020 7:24 pm 
Diamond Grade

Joined: Thu Jul 15, 2004 1:56 pm
Posts: 1315
Ulysses wrote:
The first thing is inadequate amount of powder. The second thing is inadequate amount of shot. Those two things combined resulted in inadequate gas pressure at the gas ports.

The way to test this is to cut open a couple of Win Universal shells and take enough powder to weigh the same as your comparison reload of 17.3 grains. Then add enough shot to make it 1 1/8 ounce weight as in your comparison reload.


That is really not a good idea.

Look I added enough, 2 grains of powder, in my load.
I used 17.3 of clay dot.
I added 1/16 of shot.
My velocity was actually 2 fps less than the factory load.
I added 13% more powder, and my velocity dropped 2 fps.
My loads worked the action and threw the shells quite well.

Now imagine the factory loads are near maximum pressure,
which they should be, because they can make them cheaper
that way, and higher pressure loads burn cleaner. So we
got a shell running near maximum, and it is putting out
1160 fps. Now we increase the powder 13% and increase
the shot by 6%, what do you suppose is going to happen
to pressure? INCREASE. How much? who knows, that
is why it is not a good idea.
------------------------
My test proved beyond any doubt, in my mind, that
the main problem with Winchester Universal not cycling
many gas guns is the powder is just too fast burning.

This backs that up:
--------------------------------
Understanding max chamber pressure:
Max chamber pressure is the maximum that is achieved.
A load of fast burning powder obtains it's max pressure
when the shot charge has only moved very little. For
sake of understanding lets say it achieved the max
pressure when the shot charge has only moved 1/2 inch.
Lets say that pressure on a 20 ga target load may be
11,000 psi. Now look at what happens when the shot
charge has moved 1 inch. It now has twice as much
space to contain the gas. Since it has twice the
space, the pressure is dropped by half. So if max
pressure was 11,000 psi when the charge moved 1/2
inch then when it has moved to 1 inch the pressure
is dropped by half, and now the pressure in the
barrel is 5,500 psi.

As the shot charge moves on to 2 inches of travel the
space available for the gas has now doubled again,
and now the pressure has cut in half again, so once
the shot has moved 2 inches the pressure has now dropped
to 2,750 psi.

Likewise when the shot has moved 4 inches the pressure
is dropped by half again, now down to 1,375 psi.

At 8 inches of shot travel the pressure is now only
687 psi.

If your gas ports are 8 inches from the chamber, then
the gas ports see 687 psi.

Now take a slow burning powder. Lets say this powder
develops 10,000 chamber pressure, fully 1,000 less
than the fast burning one. Also lets say it burns
so slow that it does not get its max pressure until
shot has moved 1 inch. It takes twice as much time
or space to develop its MAX because it is burning
SLOWER. With this powder, when the shot moves 2
inches the pressure has dropped to 5,000 psi.

When the shot has moved 4 inches the pressure has
dropped to 2,500 psi.

When the shot has moved 8 inches the pressure has
dropped to 1,250 psi.

Now which one has the most pressure at the gas ports?
The slow burning does, in this example the pressure
is twice what the fast burning powder was even
though the slow burning had less MAX chamber pressure.

To get low power loads to work your gas action,
you are better off using the slower burning powders
and more of it, to get that pressure at the gas
ports. This does not apply to guns like the versa
max that have it's gas ports right up in the chamber
area.
---------------------------------------------


Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Wed Dec 23, 2020 9:28 am 
*Proud to be a*
*Proud to be a*
User avatar

Joined: Sun Jul 27, 2003 3:37 pm
Posts: 19474
Quote:
That is really not a good idea.

Look I added enough, 2 grains of powder, in my load.
I used 17.3 of clay dot.
I added 1/16 of shot.
My velocity was actually 2 fps less than the factory load.
I added 13% more powder, and my velocity dropped 2 fps.


You're proving my point while at the same time drawing incorrect conclusions about WHY things changed. You took a very fast powder (Clay Dot) and added 2 grains of powder. You also added 1/16 ounce of shot to the load. This is essentially what I suggested doing. The result you got was a load that operated the gun just fine. The reason it operated the gun just fine is because with the increased powder and increased shot, you now have enough to generate sufficient pressure at the gas ports to operate the action.

Quote:
Now imagine the factory loads are near maximum pressure,
which they should be, because they can make them cheaper
that way


Factory loads, for the most part, are NOT designed to operate "near maximum pressure". There are too many old guns out there in questionable condition for manufacturers to even consider doing anything like that. The lawyers and accountants determine what is made today, not the engineers.

The reason Winchester uses only 15.3 grains of powder and only 1 1/16 ounces of lead in their Universal loads is because they save the most money that way in these crap loads. About 18 to 20 years ago when the Universal loads came out, they were pretty decent loads for a low cost loads. I shot a bunch of them and they were stout in recoil with a full 1 1/8 ounce of shot and plenty of powder to propel the loads to around 1200 fps. They operated my autoloader guns with authority. Today, the Universal shells have turned into crap.

You can continue to believe what you want, but the reason the Universals don't work well in many autoloaders is because Winchester has cheapened the shell so much to save money. It's not that they have found some magic fast burning powder to use. It's because they know that many people who buy the shells today are looking to pay the cheapest price they can. And "cheap" is exactly what they get with these shells.

_________________
Please post For Sale items in the proper Classified section.

Semi-Auto Classifieds is ONLY for Complete Semi-Auto shotguns.
Over/Under Classifieds is ONLY for Complete O/U shotguns.
Items other than a complete shotgun go in OTHER Classifieds.


Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Wed Dec 23, 2020 10:20 am 
Crown Grade

Joined: Thu Jul 31, 2008 11:12 am
Posts: 5703
For the OP. All this is fine if you use published loads. Those who apply metallic loading rules to scattergun loading are gambling with their eyes, fingers, and possibly lives. You don't know what powder Winchester uses. They for the most part don't use what's available to us for powder. I see what looks like working up a load. That's not good for shotgun loading. Win Universal is a crap shell with a crap hull. It shouldn't be used for a baseline, you don't know what powder Winchester used in that lot. Any load that's unpublished should be sent out for testing by professionals. How a gun cycles and velocity measured by a home gamer means nothing. You have no clue what your pressures are. I see lots of guess work in loading shells and experimental unproven modifications to a gun. This is real testing for reloads.https://www.precisionreloading.com/docs ... TION-2.pdf
In shotshell reloading, there are NO pressure signs, until you get way over the maximum pressures.
You simply cannot rely on any sign/condition, to determine when you have reached Max safe pressures.


Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Wed Dec 23, 2020 1:52 pm 
*Proud to be a*
*Proud to be a*
User avatar

Joined: Sun Jul 27, 2003 3:37 pm
Posts: 19474
Joe,

Just for the heck of it, I looked at my records and found where I had cut open a couple of the Winchester Universal 1 1/8 ounce 3 Dram shells back in 2003 and weighed the contents.

The first shell had 504 grains of shot and 18.0 grains of powder.

The second shell had 494 grains of shot and 19.2 grains of powder.

Both of these shells were actually OVER weight on shot since 1 1/8 ounce is 492 grains.

Also, both of these contained considerably more than the 15.3 grains that you found in the shell that you cut open.

Although we don't know what powder Winchester is putting in the Universal shells, I haven't found any 12 gauge shell recipe with ANY powder that lists as little as 15.3 grains of powder for a 3 Dram load of 1 1/8 ounce of shot.

_________________
Please post For Sale items in the proper Classified section.

Semi-Auto Classifieds is ONLY for Complete Semi-Auto shotguns.
Over/Under Classifieds is ONLY for Complete O/U shotguns.
Items other than a complete shotgun go in OTHER Classifieds.


Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Wed Dec 23, 2020 2:23 pm 
Crown Grade

Joined: Thu Jul 31, 2008 11:12 am
Posts: 5703
Working up loads under can become just as dangerous as over. Especially in a semi auto.


Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Wed Dec 23, 2020 8:02 pm 
Diamond Grade

Joined: Thu Jul 15, 2004 1:56 pm
Posts: 1315
They use different powder at different times in factory loads.


Top
 Profile  
 
 Post subject: Re: A300 gas system maintenance
PostPosted: Thu Dec 24, 2020 8:21 am 
Crown Grade

Joined: Thu Jul 31, 2008 11:12 am
Posts: 5703
When it comes to reloading, experimenting using unknowns and jerry rigging guns is a recipe for disaster.




Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 30 posts ]  Go to page Previous  1, 2

All times are UTC - 6 hours [ DST ]


Who is online

Registered users: AJ-M12, amboy49*, Bakerloo, bbush, Bing [Bot], Blackdog56, BPdiver, casonet, castnblast2, Colt99, cookoff013, Curly N, cwtech, dannyd93140, Dave Holmes, Denver1911, Dmc57, double20, dpe2002, drawdc, DuckDog12/3, ebcjr, ellisjre, EricB, faas001, fiddlesticks, GACory, GE-Mini-gun, Google [Bot], Google Adsense [Bot], Google Feedfetcher, HenryVac, hopper810, JacksBack, JonnyRocket, Jreedtn, KRIEGHOFFK80, Lacyb, liveblues, Long Range, lossking, MacAR, mactownbob, Maser, McFarmer, MemphisRebel, NewToClayMan, nhithaca, ohio mike, OklaMike, OldStufferA5#1911, oldthompson, P.Muerrle, Pine Creek/Dave, PJDiesel, pops78, Quacklw81, raymond525, Rooster booster, Rudolph31, searun, shacked, shriker, Steeler [Crawler], SuperXOne, Tomf, treeduck71, twfran, viking, wdavis8679, winmod21, Winston Wolf, ysr_racer


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group    - DMCA Notice