I use 1-16 Keith it helps to elminate the issues of nose slump and the results are smaller 200 yard groups and it has worked out very well for me. I actually like 1-10 allot more but it has caused some minimal leading issues in one rifle but nothing real serious just a bit unwanted by me.

I use 9+1 coww/lino for most bullets for:
BPCR, regular and Magnum Handgun, CBA Vin Mil, and Deer Hunting.
Works very similar to 16+1 Pb/Sn. Noted my 9+1 works
better for me for BPCR, including greasers and PP bullets.
Also use straight Lino for CBA Vin Mil , e.g. 30-06,etc.
But for my 25-20, I switched to 19+1 Pb/Sn
May also try16+1  for Schuetzen this year.
beltfed/arnie

I started out using 30-1 because that's what I was using in BPCR Silhouette when I got into Schuetzen. 

A few years later I changed to 25-1 because that's what most everyone I shot with was using. 

As I got more serious about Schuetzen I changed to 20-1 on the advise of John Louis.

My scores have improved along the way, but I believe that has more to do with trigger time, experience, and lots of good help and advise from fellow competitors.

I never did any side-by-side testing with alloys. 20-1 is working for me and I see no reason to change. If I had the time I would do some testing now trying even harder alloys. Unfortunately that's not in the cards at this time.

JerryH

My Stevens Pope .33-47 shoots slightly better with 20 than 30. The 30 did not show 250 potential. I don't have any precise numbers any more.  The shooting was done over 25 years ago.  Interestingly, after the lube has dried for a year or longer, the 30 improves enough it seems to shoot as well as the 20.  That is a casual observation.  I have not tested 20 against 30 using year old bullets.

Keith
You have raised a good issue and worthy of extended discussion. IMO, bullet design plays a significant role in choosing the proper alloy. 
For 200 yard target shooting, a blunt, Pope-type bullet will work with a wide variety of alloys in my experience. A long-nose spitzer, will likely require a harder alloy to prevent nose slump. The fly in the ointment on my nose slump premise is that unless you can capture fired bullets in undamaged condition, there's no real way to analyze what is actually happening.

John,
I'm curious how bullets dug out of the berm could be examined for nose slump? Wouldn't striking the berm deform the noses, and taint any inspection for slump?

I've heard a lot of talk about nose slump, and it's affect on bullets, but never figured out how people measured it, or captured bullets without damaging the nose and creating the slump in the process. Even snow will have some impact effect on bullets.

Vall Barry Darr built and preformed catch box testing and found nose slumps from five thousandths on up.