"progressive" powders and tight patterns

[Double Lab]

as a waterfowl load- i am concerned about its reputation for poor cold weather performance

I used it for years in some cold wet weather and it performed as expected. I'd have to look up my load data but if memory serves me right I used the Federal 209/209A which is a hotter primer and the RXP12 PP29928 wad which I have an ample supply of if you are interested.

[StubTwist]

Did a little research on the interweb what I could find with 572... very little out there by the way.....

I guess 572 was developed as a replacement for discontinued IMR 4756. I really liked 4756 and I had no issues with it.

Last time I was at a gun shop in NH they had it on the shelf... probably go and pick up a bottle next time I'm there.

[Harry Collins]

I thought 7625 was no longer being produced and that it had the poor reputation in cold weather. I have just a teasing amount left. 4756 is my 1 1/4 oz 10 gauge powder.

[OH Osthaus]

Originally Posted by Harry Collins

I thought 7625 was no longer being produced and that it had the poor reputation in cold weather. I have just a teasing amount left. 4756 is my 1 1/4 oz 10 gauge powder.

neither is made any longer , however I have a supply of each
i have used the 4756 very little - and base my concerns on the discussions on this board

such as http://parkerguns.org/forums/showthr...highlight=4756

[Double Lab]

I also used 4756 in my 20 ga. loads for years until 20/28 came along.

[Richard Flanders]

I think the "famous" 1330fps, 1-1/4 oz load is 3-3/4dram equivalent, not 3-1/4. That's what all my old and new boxes read.

[Cold Spring]

Deleted - duplicate

[Cold Spring]

Rick, I think you'll find that single-base 7625 or better yet 4756 are as close as you're going to get to DuPont's progressive "Oval" or the Western Powder Company's equivalent that used a different technology. Although both were called progressive burning they might have been better called "slow ignition".

Just as an aside I've read for years now that 7625 can be erratic at cold temps and I wonder if that's because of gents loading to VERY low pressure and having plastic wad gas sealing problems, or possibly some correspondents just repeating what they've read? A few years ago I debunked it at least for myself by leaving a bag of 7625 loaded 12-gauge shells outside overnight in sub-zero temps in the bed of a pickup truck, and shooting 100 of them the next morning on a sporting course when the ambient was in the negative Fahrenheit numbers to start out. They all went off with authority with no perceptible recoil reduction as compared with shooting the same loads at normal temps. The IMR chart showed pressure at about 8000 psi, temp not stated but probably 70-80 degrees in a ballistics lab. Pressure was undoubtedly lower when I shot them that morning on the sporting course.

Lastly, if you shoot 2-3/4" shells in that LCS Long Range/3-inch chamber you'll probably lose about 8-10% efficiency (pattern percentage) at 40 yards. That's with lead shot.

frank

[OH Osthaus]

Thanks Frank

I'll give them both a try - the 12 gauge loads will not be seriously low pressure- the guns don't need it - no need for roman candles though

i'll also pattern for the difference in the 2 3/4 and 3" in the Smith

i also will be interest to find out what pattern difference there may be between lead and Nice Shot or Bismuth

[Carl G. Bachhuber]

My go-to duck load during the 'lead years' consisted of 1-3/8 oz of high antimony #5 shot and whatever Winchester listed as their max charge of W571. I used it in AA or Peters blue 2-3/4 cases. I believe claimed muzzle velocity was supposed to be 1330 fps. If you fired enough of those you would get a nose bleed, but they really worked. I had no problems with temperature and I did a lot of shooting when it was well below 32 deg. So today I use 1-3/8 of bismuth or tungsten polymer, which seem to work quite well. Also in my old age I have found that if I slow down the muzzle velocity a bit pattern percentages go up.
C.G.B.