Well there has been an major increase in emails on this subject, particularly since the majors are coming out with smaller than 223 varmint cartridges and folks are interested in trying out...
This was posted on a thread here, but it will hopefully answer some of the questions I get a lot of...
These are guidelines, not gospel..they work for anything I have ever tried, but as soon as I say that, someone presents some case that no one else on the planet uses...apply this from the 17 Fireball on up, I have no idea of the results in things like the 14 Walker etc...
1. Start out with pistol primers if need be.. they are softer...
2. Determine max case capacity for the case you are using Blue Dot in.. to do that, fill until the case overflows...scrape off the excess until it is flush with the case mouth... then weight the charge...
3. Take 20% of that figure.. that is your minimum charge. and will not result in a squibb load...START AT THIS POINT...
4. 40% of the full capacity figure is the place to start working up slower...start working up in smaller increments here..like 1/10 of a grain...
5. 50% is where the max charge should be lurking somewhere around...
the smaller the case, the smaller increments you work up, especially at 40% Full Case Capacity or more...
case shape and capacities can vary the max point here..
for instance a 284 and a 280 case both have the same capacity... but the short fat case of the 284 is more condusive for B/Dot efficiency vs the 280 case... the 284 will usually run 60% of full case capacity, but the 280 will only run about 50 to 52% safely...
Blue Dot likes short fatter cases than it does long skinny ones..for max capacity, not accuracy..there is no real difference in accuracy potential..
if someone was doing a wild cat, and wanted to use Blue Dot.. and say the bore desired was 20 cal.. if they were looking for efficiency, I'd say use the 20 Tactical.. if they wanted max velocity, without being overbore, I'd recommend either the 20 BR case, or if they wanted a little more max velocity then use the 22.250 or 22.250 AI case....if they were looking for max efficiency, I'd recommend the 222 case necked down first, and the 221 Fireball case next...the fireball case would be my choice to work with 32 grain bullets, and the 222 case would be my choice for efficiency with 40 grain bullets..
Blue Dot doesn't get trickier on smaller cases, just the parameters get tighter tolerances is all...
above 40% full case capacity work in 1/10 grain increments...
more time consuming yes.. safer tho, yes..
worth the time investment in the long run, yes....
one last thing on primers.. pressure signs show up faster with pistol primers, because they are softer.. once one has a comfort level, then they can move up to rifle primers.. I usually don't see the need for mag primers, even for light loads with Blue Dot...they will work, but are not needed and the max load should be reduced a little to compensate.. they will generate higher pressures without any increase in velocity...
IMPORTANT NOTICE..Recommended procedure..
To avoid a possible double charge, always charge a case and then seat a bullet, before going on to the next round..
I also recommend weighing each charge, instead of using a powder thrower.. I never use one, with any powder, as I prefer a beam scale and a Lee Dipper.. and trickler..I also do that for any round with any powder...
If you are in a panic about a double charge, or have sloppy load bench techniques, then use a powder that is too slow for your case and you'll never have to worry about a double charge...
Example.. use 4320 in a Fireball or Hornet case......
Safe reloading technique and paying attention is the handloaders responsibility...
like doing dumb things like.. well Blue Dot and Red Dot are both powders with the name of Dot in them and both are made by the same company, so either one must have interchangable load data...
or H 335, and H 414, both look the same and both are made by Hodgdon, so their load data must be interchangable...
or RL 7 and AA # 7 both have the same number in them, so they must be interchangable....
Mistakes like that are just plain moronic.... but the sad thing is when someone gets hurt from doing something moronic......it isn't funny anymore..
So pay attention and follow instructions....
Info I put forward are guidelines but not gospel.. if they scare you for some reason, then don't use them.. know what you are doing.. if you don't, then it is a good sense of practicality to realize you are messing with something you have no business messing with...
like any load, blue dot loads are safe within their parameters...
it is your job to learn or know what those parameters are...and sometimes what is safe in one brand of brass even, becomes unsafe in another brand, because one case is much heavier and has less capacity than the other...
Last edited by Seafire; 02/19/08.
