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Anyone else using RL-17 for there creedmoor? Its listed in the hornady book but not on alliance web site for reloading. Works great though. Best grouping was with 42.0 gr. According to my ballistics app on my iphone, doesn't go subsonic until a little after 1500 yards. Would like to try H4350 but can't find that anywhere. Did try Superformance but RL-17 works better with less powder used.
Your velocity should have been better than you can get with 4350.
I have used Reloader 17 in the past in the Creedmoor with good results.
My shooting bud and I have done some preliminary work with RL17 and 3 different 140g bullets. With the chosen load for each bullet, we found we are exceeding book velocity (2725) with a powder charge below max charge wt (42g). I will qualify this by saying that we ran only 3-4 rounds of each over the chrono....and they were shot out of a 28" x-caliber barrel.
Just something to watch for, depending on how you view lawyer loads, velocities, pressures, etc.
Seems someone here has done some work with RL17 and temperature......was that you Robinhood?
I have....and RL-17 is not as bad as everyone makes it out to be...assuming your not running a hot load to start with...it creates more velocity and less pressure because it's double based.
No signs of over pressure. 42.0 gr is max load according to hornady reload book. Am getting almost 100 fps more than what the book lists too. Alliant web site shows RL-17 to be for magnum loads primary or medium rifles secondary. Will stick with this until I can find a better powder. I chrono'd 2795 fps average of 5 shots.
http://www.alliantpowder.com/product...reloder17.aspx
Went back out today to confirm this load of 42.0 gr of RL-17. Could probably go up a notch or two but think I will leave it as is. No pressure signs at all and provided my ballistic app is correct, goes subsonic at 1514.67 yards. Been looking for a better scope than the SWFA 20X SS thats on it now. After todays shooting I came home and ordered a vortex Viper HS-T 6-24X50 w/ VMR-1 MOA reticle. Wish I could have afforded a FFP scope but this will have to do for now. Wanted a Burris XTR II 4x20 w/scr moa but now where available.
"Better" than Superformance?
RL-17 is progressive, but not nearly as much as Superformance. As such Superformance is much more efficient, but if absolute max speedd is your game, YMMV.
You shouldn't use "Signs" of pressure for anything, use a chrono. But if you think you can stare at your brass and Devine pressure, the progressives will leave you guessing.
http://i78.photobucket.com/albums/j8...pskz7cqnti.png
http://i78.photobucket.com/albums/j8...psrz6rkepr.png
I never could get the groups with reloader 17. When you shoot 60 + rds 1000 yds at a 5"circle you need consistency.
I just came across RL-16 that came out earlier this year while scanning the web. Looked it up. States its a little hotter than RL-17 and primary for medium rifles and magnums is secondary. Opposite of RL-17. Anyone try it yet and compare it to RL-17?
Robinhood, what was your load that wasn't working for you?
Darrker, can you explain a little more on efficiency of Superformance?
So if you look at the two Pressure Traces above, you can see the actual curve of the powder burning. You can see that the curve of RL-17 is "rounded", or somewhat like a plateau at the peak. Regular, or non-progessive powders are a very sharp peak and fall. The one trace of Superformance has a wider plateau at the peak. This means that the burning curve matches the expansion and flow down the bore, more closely. So you get more "push" at a given pressure peak.
In the two traces above you can see that RL-17 max loads are @ 2750 fps at 60,000. Where the Supr is only 100 fps behind, but that velocity happens down at 50,000 psi operating pressure.
A thing to remember is that Superformance being as progressive as it is, is that the burning curve changes shape with pressure. So the harder you run it, the less efficient it is. The curve begins to get "peak-y" like a regular powder. In the end, the max velocities are identical at the same pressure. But as you lower pressures, Superformance becomes VERY table top, and at lower pressures gives much more velocity returns at any given pressure. At least that is what our Pressure Testing showed over a few lots of powder. Because of the shifting curve, and the fact that powders never burn linearly, you can't reliably just do some simple math and see what pressures you are running. You can certainly do some correlation, but don't expect it to be more than that. The way to know pressures is to measure.
When we began pressure testing powders and rifles, I made an assumption about what the Starting and Max pressures from manuals were. Turns out with one powder, my assumption of what it's "happy" pressure range was, was actually pretty close. But it doesn't hold true for all of them. Also remember that if you load by weight in Grains, that grain number is not a fixed thing. There is a VERY good reason why powder bottles say "drop loads 10% when switching lots". My current 8# bottle of Superformance is about 8% different than the testing done by Hornady.
Here is a pic of my range trip with superformance. Did 44.0, 44.2, 44.4, 44.6, and 44.8 grains (Top left, right, middle, bottom left, right). With your explanation, and looking at my target, seems 44.8 may have been less efficient.
http://i601.photobucket.com/albums/t...psxdzutaei.jpg
I believe more accurately, R17 is treated throughout the grain and the burn rate is and stays controled, pressure peaks and stays there longer. Other to do the same have to do a higher spike.Quote:
Originally Posted by LongRange
Just double based does not do that.
A lot like a good diesel, hits the peak toque and stays there on up to the limiter.
Your targets look very much like mine did a couple of days ago when I tested out a few loadings of Superformance and 140 Amax's. My first Creedmoor with a Criterion barrel and 140 Amax was awesome with Superformance. Most 5 shot groups were in the 3's and high 2's...but the heavy hunter Shilen I have now does not like that combination at all....having better groups by far with Reloader 19 and Ramshot Big Game. Going to work with RL-17 and some 123gr Noslers later this week.Quote:
my range trip with superformance
I see alliant released reload 16 so am on the hunt to try that. May give superformance another try but seems you need more powder than RL-17 to get the same results. But as Darkker put it, it could be better. May try a little more. Just got my new scope in so it gives me a reason to try another batch.
Hit the range today to try out the new scope, and push RL-17 a little further. Asfter some shots with what I think were good with 42.0 grains, tried 42.2 and 42.4. 5 shot groups with 42.2 averaged 2790.4 fps. 42.4 averaged 2808.24 fps. Brass looked good with 42.2. Had 2 slight case swipes at 42.4 grains. Groupings were good on both. Didn't take any pics of the targets this time. May stick with 42.4 after I get the info in my ballistics calculater and see the data.
Scored a 8 lb jug of H4350 today. Will be loading up a set to try when it gets here. Hope its worth the hype I hear about it.
I bumped this thread because I would like to see some results? or the last post. I just got my Creedmoor and I am searching for some advise.
I have had as good or better luck with rl16 and rl17. Accuracy almost identical to h4350, but much better velocities. I have not experienced temp sensitivity issues with rl17 but many others reportedly have. That's why I'm now using rl16 mostly.
I sold that rifle not long after my last post. Used the funds for a 338LM Savage FCP. Been considering getting another one but can’t decide if I want bolt or AR. Had fun developing loads for the 6.5CM. Been considering the 6MM more though if I do get another rifle. The GRS has my attention for now. How is RL-16 working out? RL-17 worked great when I used it.
H4350 is far less temp sensitive than double base powders, H4350 = 0.16 fps change for every degree in temperature change.
The military changed from RL15 to IMR-4064 in their long range .308/7.62 sniper ammunition due to the temp extremes in Afghanistan and Iraq.
NOTE, the number to the right of the type powder below is the fps change for each degree of temperature change.
https://i.imgur.com/33XPgx3.jpg
bigedp51 - Thanks for sharing that chart
Couple weeks ago I tried out two comparison loads, identical but with one difference; H4350 vs RL-17 at 750 yds using Peterson SRP brass, 142 SMK seated .025 off, CCI450. Results were the H4350 made a nice 5 shot group on the steel whereas the RL 17 was less consistent although faster and flatter. Both loaded to best speed and accuracy that I've found on my particular set up. Not exactly a scientific test, but the reputation of RL17 being a bit more sensitive seemed to prevail.
Yesterday I shot a jump study in the 6.5. Peterson brass but LRP this time. Previous best load of 41.9 of RL 17 and 142 SMK developed on a 70 F day was a bit too hot on this 70 F day with the jump set at -.030. Got ejector swipes on all 5 cases. At -.025 and closer, no swipes. Amazing what .005 less case volume can do.