dominion arms 12 gauge 8.5" or 12" witch one to buy
- Thread starter black sunshine
- Start date
Here's a little bit of substance.... Post number 2, but there is other good info as well.
www.shotgunworld.com/bbs/viewtopic.php?f=12&t=238661&start=0
You read the writings of an idiot. Of course the powder is burned
in the first 18 inches of barrel. Actually it is burned in about the
first 1/2 inch of the barrel. Modern powder requires pressure in
order to burn, and if enough pressure is not there it will fissile out.
Once it gets this pressure it burns very fast, like in the first little
space while still in the chamber. This is where max chamber pressure
is accomplished. A typical load might be that this powder is burned
and generates a chamber pressure of about 10,000 psi when the
shot charge has only moved about a half an inch. From there on
the pressure reduces. If max pressure is at 1/2 inch, then when
the shot has moved one inch, the exploded gas has about twice
as much room to house it, so the pressure is reduced by about
half. Now the pressure has reduced to about 5,000 psi. and
the shot has moved twice as far, one inch if max pressure was
at 1/2 inch. The pressure continues to reduce as the shot moves
further down the barrel. When the shot again moves out to 2 inches
of travel the gas has now twice as much space as it did when the
shot had moved to 1 inch. Now the pressure drops by half again.
Now the pressure is only about 2500 psi. This continues on down
the barrel. As the shot once again moves the distance it already
moved, the available space is now doubled and the pressure
reduced by half again. Here is the way pressure and distance
continued down the barrel:
pressure___distance
10,000____1/2 inch
5,000_____1 inch
2,500_____ 2 inches
1,250_____4 inches
675_______8 inches
338_______16 inches
169_______32 inches
So you can see that as the barrel gets longer the amount
of pressure drops. A longer barrel gives you more velocity,
but as it gets longer, the gains become smaller, because
the remaining pressure is doing less and less.
This idea that 18 inches is magic and anything longer than this
gives no more velocity is pure fiction, and the explanation for
this being that once powder is burned it stops putting pressure
on the shot load is also pure bunk.
www.shotgunworld.com/bbs/viewtopic.php?f=12&t=238661&start=0
You read the writings of an idiot. Of course the powder is burned
in the first 18 inches of barrel. Actually it is burned in about the
first 1/2 inch of the barrel. Modern powder requires pressure in
order to burn, and if enough pressure is not there it will fissile out.
Once it gets this pressure it burns very fast, like in the first little
space while still in the chamber. This is where max chamber pressure
is accomplished. A typical load might be that this powder is burned
and generates a chamber pressure of about 10,000 psi when the
shot charge has only moved about a half an inch. From there on
the pressure reduces. If max pressure is at 1/2 inch, then when
the shot has moved one inch, the exploded gas has about twice
as much room to house it, so the pressure is reduced by about
half. Now the pressure has reduced to about 5,000 psi. and
the shot has moved twice as far, one inch if max pressure was
at 1/2 inch. The pressure continues to reduce as the shot moves
further down the barrel. When the shot again moves out to 2 inches
of travel the gas has now twice as much space as it did when the
shot had moved to 1 inch. Now the pressure drops by half again.
Now the pressure is only about 2500 psi. This continues on down
the barrel. As the shot once again moves the distance it already
moved, the available space is now doubled and the pressure
reduced by half again. Here is the way pressure and distance
continued down the barrel:
pressure___distance
10,000____1/2 inch
5,000_____1 inch
2,500_____ 2 inches
1,250_____4 inches
675_______8 inches
338_______16 inches
169_______32 inches
So you can see that as the barrel gets longer the amount
of pressure drops. A longer barrel gives you more velocity,
but as it gets longer, the gains become smaller, because
the remaining pressure is doing less and less.
This idea that 18 inches is magic and anything longer than this
gives no more velocity is pure fiction, and the explanation for
this being that once powder is burned it stops putting pressure
on the shot load is also pure bunk.
Neither is ideal for a sporting gun mainly due to being difficult to swing smoothly on game ( this is the sporting forum) 
but to each their own. There will be a loss of velocity with either barrel length as the gases will still be expanding at those lengths even though the powder will be burnt, but the pattern will be dependent on the chokes to a large degree and not the shot velocity.
but to each their own. There will be a loss of velocity with either barrel length as the gases will still be expanding at those lengths even though the powder will be burnt, but the pattern will be dependent on the chokes to a large degree and not the shot velocity.thank you (Eric_911) .
im considering it for a, camp gun/bear defence/slug gun/and possibly (upland game), such as - grouse, squirrels, and rabbits in dense, northern Ontario bush. kinda gun.
Maby 30YDS .
is a good pattern achievable at this range .
im using a rem 870 sps waterfoul now and frankly its a bit much (huge) as far as im concerned. so hoping this will fit quite nice.
im considering it for a, camp gun/bear defence/slug gun/and possibly (upland game), such as - grouse, squirrels, and rabbits in dense, northern Ontario bush. kinda gun.
Maby 30YDS .
is a good pattern achievable at this range .
im using a rem 870 sps waterfoul now and frankly its a bit much (huge) as far as im concerned. so hoping this will fit quite nice.
This is right up the alley of several people on this board who do this stuff with these types of short shotguns all the time. I would defer to their experience on the subject....
If it were me though, I would get a Dlask 12.5 870 barrel, and get it threaded for chokes. The Dlask barrels are meatier than the Chinese ones, and will be much easier to thread for chokes. Dlask can even do the work for you. Detractors are that they're a lot more expensive than the alternative Chinese barrels... And, they are really heavy.
The Dlask barrels will run 300$, before threading and chokes, and before the installation of the ball detent (I believe)
(Not shilling for Dlask. Just like their stuff)
Evidence of the uselessness of this configuration of 870 can be found on the EE. Look for "never fired" or "only 10 slugs down the pipe" in the description. Seriously, compact versions serve a purpose maybe for bear defense, but I suspect most buy them to take "selfies" to post on their Facebook profiles. If you are serious about hunting or clay targets, get a longer gun that fits your body frame. The 870 is a good gun.
1300_stainless
Regular
- Location
- Nova Scotia, Canada
I've had both. The recommendation to get a 12" one in case you want to swap barrels is a good one. The 8.5" is a blast but has limited practicality and a pretty big spread. If you don't think you'll want it for anything other than defense then the 8.5 would probably work and keep you a bit more compact. Both could benefit from interchangeable chokes. Also a smith who knows what they are doing can thread a pretty thin barrel for the right type of chokes, I've had it done.
i have a 8.5, my roomate's 870 has a bunch of barrels as well at a 12, my 8.5 is tons of fun it shoots big fireballs, however it is a toy, i have gotten ditch chickens and rabbits with it but less than ideal, its my hiking/hanging around camp bear gun. its too loud to hunt with, normally when walking through the woods looking for grouse or rabbits im guessing you dont wear ear plugs, just #8 shot loads are loud enough and have enough concussion to hurt, and your ears ring for days after just a couple shots (im not being a wimp i shoot my sxs 12ga with out ear pro all the time looking for grouse) the 12 isnt that much quieter but the cuncussion isnt there. just my .02
sillymike
CGN Ultra frequent flyer
If you find an 'older' 12", they were available with a screw in chock... So the pattern can by tweaked to your need.
Not sure what they were expecting us to fire from them, but the barrels seems way over built (on both the 8" and 12")...
Shooting them with nothing but the front bead take some getting used to. With a such a short barrel, the <natural> line of sight makes you shoot (way) high.
Personally, I like them for the sh!t and giggles effect. Shooting buckshot and full power slugs is a blast (literally)
