On the shotgun power factor topic ,it seems that no
one(to my knowledge)uses buckshot which typically starts at size SSG.
Buckshot is invariably heavier loads loads of lead shot.
I have noticed that at present most competitors are
using lighter birdshot .In vary rare instances heavier 35g AAA being the
largest shot size used.It seems that most competitors are using 28 g(1
ounce)(432gr) loads(or lighter).
Having fired both buck and bird shot of all sizes it
seems that the choice is the weight of the shot and the velocity of the
shot that make a difference on the felt recoil.This is personal choice so
whatever your load of choice , the reality is that whatevever load drops
a pepper popper (and makes POWER FACTOR) is the real consideration.On this
point I would like to point out that I have Chronographed(among others) a 28
gram no 6 hand load that drops a pepperpoppper at 30m but only factors
The power factor requirement FOR SHOTGUN = 520 . A
typical 28g load should at least reach a velocity of 1205 fps to factor at
520.If you factor 519.9 you will continue to shoot the match WITHOUT score.
In factory form the following typical loads exist
in 2 3/4 "(70mm)cartridges.
DRAM EQUIVILANT SHOT WEIGHT VELOCITY POWER
The specs for Cartridges of 2 1/2 " and
shorter in length are probably even lower in velocity and charge weight or both
HOWEVER I have never tested or used these.
The following can be deduced from abovementioned :
24g loads in factory form probably won't factor
,although depending on the manufacturer it might (barely)
28g loads in factory form are better with a slightly
better chance of factoring
(for 24 and 28g loads it seems that it is
wise to choose the highest velocity amunition if power factor is to attained)
32g loads in factory form are in all likelyhood always going
36 g loads (and heavier) in factory form always make factor
and granted they seem (subjectively) to bump harder .
The only factory loads that I have CHRONOGRAPHED is
35g NO 3=620POWER FACTOR (Swartklip) and 35gAAA =617POWER FACTOR
The position in above mentioned regard will change for
the handloader who reloads his own ammo , however very few competitors
reload(yet).A session over the chronograph may produce some alarming results
,particularly at a match.
I would be pleased to hear from others regarding
their findings since it is a matter of time before shotguns will be
chronographed at matches(maybe the 3 gun nationals ?)
So what now ? I suggest chronographing your
favourite load and ensure that it makes the cut-off.
"don't get caught with your power factor