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Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 10:37 am
by Distant Thunder
I'm working on a load for my .44-77 SBN using Swiss 1 1/2 and a bore diameter paper patch bullet with the goal being the best accuracy possible for Creedmoor matches.

I had a limited amount of a 2016 lot of 1 1/2 that shot well with 86 grains at .090 compression. I am now looking to get my 2013 lot, which have a good deal of, to shoot as well. When I drop tube 86 grains of the 2013 lot into the same BACO brass and compress to the same .155" deep the 2013 lot only has .025" compression compared to .090" with the 2016 lot at the same depth.

With 86 grains of the 2013 lot compressed .025" the accuracy isn't bad at a little over 1 moa at 220 yards, but I feel it could be better. The difference in compression is due to the 2016 lot being less dense than the 2013 lot. Measuring all this out and thinking, which is where I usually get into trouble, I have to wonder is it the weight of the powder charge or is the amount of compression that has the bigger part in the accuracy of a load? Or do they both come into play?

I would have to shoot a good number of 10 shot groups with the 86 grains of 2013 Swiss to see for sure, but in early goings the two loads are pretty close accuracy wise.

Since I am shooting bore diameter paper patch bullets my cartridge overall length (COAL) isn't determined or limited by a groove diameter bullet. In fact I have found that this cartridge, the .44-77, is not overly sensitive to seating depth and I have had very good accuracy from .100" deep to .300" deep using bore diameter paper patch bullets.

With grease groove or 2-diameter pp the COAL is usually set by how far the bullet can be seated out to be up against or somewhat engraved by the rifling. So I would first find that length and then determine the minimum amount of powder to fill the case to give me the compression I want to start my testing with. I would then increase the powder volume and therefore compression to find the sweet spot. The weight of that lot of powder that gave me the volume I needed would be my load and I would write it down. Any future lots of the same powder would just be measured to that weight and the volume and compression were not really a concern. That was one of the beauties of Swiss 1 1/2, I could buy a new lot and load the same weight and accuracy was always good. The newer lots started being less dense some where in 2013 or there about. I never worried about the compression, just the weight. Life was good and loading was simple.

Now I am working backwards, from a newer lot to an older more dense lot of Swiss 1 1/2. This 2013 lot shoots extremely well in my .45-70 and .40-65 so it's good powder. From the history I have with this lot of powder I know it likes more compression than the .025" that I noted above. I really don't want to load more powder even though I could. The 86 grains is shooting well, but would it shoot better with something closer to .090" compression like it has in my other two rifles? I will have to test that to know, but I was wondering what others might think about my subject question? Any experience with this?
Any interest in knowing which matters?

The other thing that I was thinking about is this. If 86 grains shoots better with .090" compression, would 84 grains shoot well with .090" compression. I would just have to change my seating depth to keep the same compression. How about 82 grains?

I did test 80 grains, 82 grains and 84 grains seated deeper and all to the same depth and it shoot better as the compression went up. Unfortunately I did not note the amount of compression at all. I'd have to go back and see how much compression 84 grains had.

What do you all think?

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 12:05 pm
by art ruggiero
try a thicker wad to increase comp and see what happens art

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 3:51 pm
by desert deuce
What do I think :?: :idea: :idea: :idea:

I think you shoot too well already. Why would I help you improve :lol: :lol: :lol: :lol: :lol:

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 4:07 pm
by Distant Thunder
Dang, that hurt, DD! :lol: :lol: :lol:

I would help you! Except you use those greasy grooved bullets and I don't know nothing about them. :P

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 5:11 pm
by desert deuce
See, see............any 'good' advice I could credibly share is concerning grease groove bullets and you seem to abhor the facts. :P

So why bother? :mrgreen:

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 5:50 pm
by Distant Thunder
My thoughts and resulting questions are about powder compression vs. weight with Swiss 1 1/2. That's not just a paper patch concern! I would think a greaser like yourself would have thought about it too and be willing to share. It seems maybe not.

No matter, I've loaded 86 grains with .025" compression and. 090" compression and all else the same except the adjustment to the COAL to get the two compressions. I will shoot those tomorrow if the rain stops and that will be one more step toward answering what seemed like a simple question.

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 6:29 pm
by bruce m
jim,
i hate to be the bearer of bad tidings.
you have no choice but to do the testing.
the problem with compression vs charge wt is that generally if you change one you change the other - 2 things at once.
of course the best way is to only change 1 thing at once.
as some have suggested, keeping the same coal and adjusting compression using wads is worth a try, but you are still dealing with 2 things at once.
sometimes being a perfectionist is a cross to bear, but you just have to wear it.
my 40/72 uses around 85 gns of swiss to bring the wad to the top of the case, and the bullet design requires about 1/10 to 1/8 compression to put the diameter transition on the rifling.
however one lot of powder took 90 gns to do the same thing.
it turned out that both loads shot about the same, but you cannot generalize on 1 example.
if i can get 1 moa vert at closer ranges, it might well be up to 2 moa for the same load at 1000.
tighter would be better, but a 2 moa vert load at 1000 will always in my case be wider than it is high.
they say "the wind is your friend"
to maintain a healthy friendship, both parties must have input into the relationship, and the wind does this.
to get good scores we must also put into the relationship with the wind.
bruce.

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 7:02 pm
by Distant Thunder
bruce,

I'm not looking for a short cut. I knew when I ask the questions I did that I'd have to test my thoughts myself if was ever going to have the answers for my rifles. That is not a problem, more shooting is a good thing. The day will come when I will say to myself, the only one who will probably listen, "Gee, I wish I had shot more when I was still able!". So rounds are already loaded and testing will happen.

Somehow I though a discussion of the subject would be of interest, there I go thinking again! I'll put my money on the load with 86 grains and the shorter COAL resulting in more compression coming out the winner!

You may have lost me a bit with the whole relationship with the wind thing. I see the wind as an adversary, something to be overcome, be defeated. I would not stay in a relationship with anyone who lies to me, does things without telling me and behind my back. The wind is not to be trusted, you have to keep a close eye on it.

Now back to powder compression.

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 9:21 pm
by semtav
Be interesting to see what you come up with DT.
I don't go thru enough powder to have to make that adjustment, much, but i would think someone like Kurt who goes thru 2-4 cases a year would have that answer down pat.

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 11:42 pm
by bruce m
jim,
maybe you look at the wind like a good woman.
it keeps you constantly on your toes :lol:
it is however always honest, even though it might sneak up on you at times.
in answer to the rest of your post, i expected the answer you gave.
bruce.

Re: Swiss 1 1/2, compression or weight?

Posted: Sat Apr 10, 2021 11:49 pm
by desert deuce
DT, the wind was likely given a woman's name for a reason and yes you need to learn to get along with her. :wink:

After all DT, we refer to the effect of the wind as value.

Moreover, I advocate to load by volume and with a different lot of powder that volume almost always does not weigh the same as the other.

Example given Swiss 1 1/2: a 2016 lot of 55 grains volume weighs 52 grains. A 2013 lot 55 grains volume weighs 56 grains. Same volume different weights. Perhaps the reliance on weight is a symptom of loading smokeless and having that procedure stuck in the brain housing group?

Assuming a functional brain that is. :lol: :lol: :lol: :lol:

Re: Swiss 1 1/2, compression or weight?

Posted: Sun Apr 11, 2021 12:47 am
by martinibelgian
And then you have to ask yourself the question, was the better shooting the result of the increased compression, or of the shorter OAL? 🤔

Re: Swiss 1 1/2, compression or weight?

Posted: Sun Apr 11, 2021 7:25 am
by Distant Thunder
DD,

All brains seem to function, but not all function at a high level. My own seems to sputter at times, but that is corrected by a good, hot, strong cup of black coffee! Ahhhh! Time for another cup!

I have always gone by weight when transitioning to a new lot of Swiss 1 1/2. The idea being that a certain amount of the ingredients from which the force is generated will weigh the same whether fluffier or denser. That thinking has always worked well for me.

You guys can play kissy face with the wind if you want, I do not think it will buy you any favor. The wind can be used with good results, yes, but it will also come up behind you and kick you in the ass without warning. :shock: That is not someone I would call a friend! The wind is not to be trusted, but you can get along with it if you don't completely trust it and keep a close eye on it.

Martini,

There comes a time when I stop asking questions and just shoot what works! And here I is! :)

Re: Swiss 1 1/2, compression or weight?

Posted: Sun Apr 11, 2021 7:54 am
by Don McDowell
Jim IMHO the wind is something a person just has to put up with, and deal with as best you can.

Seating depth is something that comes into play a lot more than some would have you think. Especially in the paper patch world. The oft repeated only having a tiny amount of bullet seated in the case doesn't always play out. I am also of the mind that powder column height in the case to achieve the rifles preferred seating depth, plays a huge factor in accurate load, volume and weight sometimes be damned.
Shot some test loads in the 77 yesterday, some grease groove and some patched. Had to compress the charge I generally use for greasers a good bit more than I would normally like to get the bullet to chamber. Didn't shoot worth a crap, but that same charge and excessive amount of compression with the dual diameter patched bullet yielded about 2 minutes of vertical at 1000 yards.

In the end it boils down to finding what the rifle likes, the rifle really don't give a rip what you think it wants. The rifle is the one that needs to be happy, once it's happy all is well in the world.

Re: Swiss 1 1/2, compression or weight?

Posted: Sun Apr 11, 2021 9:13 am
by Distant Thunder
"In the end it boils down to finding what the rifle likes, the rifle really don't give a rip what you think it wants. The rifle is the one that needs to be happy, once it's happy all is well in the world."

Amen, brother Don!

I'm glad to have you jump in with a good perspective on the subject at hand.

I don't mix pp and gg, but back many years ago when I was young and didn't know any better I did shoot the greasy ones :oops: and I used Swiss 1 1/2 back then too. I was at that time also shooting the .45-70 for long range matches, but in a different rifle. That rifle really liked the Lyman 457132 Postel bullet. I loaded from 72 grains up to 82 grains of Swiss 1 1/2 and it always shot well. That rifle has a .200" long freebore and 72 grains with .030 LDPE wad had minimum compression while the 82 grain load had something nearing 3/8" compression.

If I had to pick an accuracy sweet spot it was in the 72 to 74 grain range, but that lacked the velocity I wanted for long range and I mostly used it for silhouette and for a few years I shot it at 800 yards only. It shot some pretty good scores at 800. The 82 grain load was not as accurate, but I won my first long range match shooting that heavier load and in so doing I came within 1 point of the national record as it was then for 45 shots. So it wasn't a bad load.

With paper patch bullets and shallow seating I have never approached 3/8" compression with Swiss 1 1/2 nor have I ever felt a need to. I don't think it would be as forgiving as it was with the groove bullets.

The thought of seating paper patch bullets deep did not occur to me with the .45-70 or .40-65 when I has using shallow seating to get a maximum amount of 1 1/2 in the case, 83 grains in the .45 and 72 grains in the .40. With paper patch in my .45-90 Shiloh and their standard GG chamber, the rifle that opened my eyes to PP, I was loading 100 to 105 grains of 1 1/2. That would have been the time to experiment with deeper seating, but I was told to seat about .100" in the case and that worked very well. The thought of seating deeper never came to me even though burning over 100 grains of powder per trigger pull did not please me when I considered the cost. Winning matches was worth the added cost so I didn't try to fix what was working so well.

I later fixed the excessive powder use by building a new rifle, my .45-70 Hepburn. At 83 grains per bang I am a happy man and I still win matches so I'm more happier!

This whole seating deeper and compression question comes from shooting the .44-77 SBN. I quickly learned that it will shoot well with the pp bullets seated anywhere between .090 and .300" deep. So I wonder, if the seating depth is not an important detail what is the key to an accurate load. It isn't a particular weight of powder because I have varied that with the seating depth. So it would appear that the amount of compression could be the key. That would mean that I could load between 75 grains and 90 grains as long as the compression was there that makes the rifle happy.

That idea should be easy to test and I find the idea interesting. With a bore diameter paper patch bullet I will have to keep a certain amount of the bullet up in the bore to have good alignment and too much of a loose fitting bullet in the case would probably bring other problems to the surface. Being a bottleneck case limits the depth enough I don't expect see any problems. At some point a 2-diameter pp bullet would become an option and I have one of those I can work with too.

It's going to be a busy summer and I have a lot of other things to do besides my shooting so I may not get to all the testing I'd like to, but I can still think about it and I do.