Reloader 33 and high pressure

[BMcKell]

I have worked up loads with Rl33 on two different rifles, a 338 LAI and a 300 Norma Imp. Both times I would get a good accurate load developed with low pressure signs and then all of the sudden they are way over pressure and sticking cases and have ejector marks. With the Norma it happened in the same shooting session. I cleaned the bore using wipe out twice thinking it was building up carbon but now I can't even come close to my previous load without high pressure. With the Lapua I switched to Retumbo and never had another problem. Has anyone else ran into this problem with RL33 and if so did you figure out the problem?

 

[Timber338]

I have been using RL33 in my 338 RUM, and have not had any problems. I have had very consistent temperature performance all the way down to about 2 degrees F. My older chronograph is not accurate enough to report actual velocity variations.

But I am curious to hear if anybody else has had this issue so tagging in. And will obviously report back if anything comes up as the temps start to warm up.

 

[Engineering101]

You are shooting some pretty high performance chamberings. I have had the problem you describe in a 26 Nosler (the king of overbore) which would only settle down with US869 and no solid copper (Barnes) bullets. I have read a couple of comments indicating that stick powder can cause pressure spikes in the really big overbore cases and the US869 can cure the problem..

In my 300 RUM, RL-33 is pretty well behaved. I'm using 97.0 grains behind a 210 Berger Hunting VLD. COAL is 3.805" which is about 0.005" off the lands. This load has done multiple 0.5" 3-shot groups at 200 yards. From what I can see RL-33 is pretty well behaved though it does appear to have moderate temp sensitivity but not near as much as RL-25 and RL-22 which uses a different technology and are thus so sensitive to temp variations as to be unusable - my opinion.

 

[brentc]

I've seen this with several powders when using virgin brass. Were you using fire formed brass during load development?

 

[BMcKell]

I fireformed them using cream of wheat.

 

[jonthomps]

Interesting. I'm currently doing load development for my 300 Norma w/ RL-33 and H1000. My loads were stout, but I ran into the same issue: some shots no ejector marks, some shots had noticeable ejector marks. Accuracy sucked. I switched to H1000 and . . . PRESTO! 3/8" groups with virtually no load work up.

I'll have 16lbs of RL-33 for sale - anyone want it, lol.

 

[Lefty7mmstw]

Interesting. I'm currently doing load development for my 300 Norma w/ RL-33 and H1000. My loads were stout, but I ran into the same issue: some shots no ejector marks, some shots had noticeable ejector marks. Accuracy sucked. I switched to H1000 and . . . PRESTO! 3/8" groups with virtually no load work up.

I'll have 16lbs of RL-33 for sale - anyone want it, lol.

if you were closer to me I'd take the rl33 off of your hands... I'm burning a lot of it here.... the biggest thing I've noticed is if you are crowding the top with this powder it will let you know it...

 

[kaseyfied]

Ya I'll take that powder. It shot awesome with my 338 lapua AI, 338 EDGE, 7MM ROUGE.... its awesome. The lapua improved was 109 grains, and shot awesome!! Never had a problem with it being too hot to shoot

Kasey

 

[JeffVN]

I've not had any similar issues running 300 gr. Lapua Scenars (and I'm running 105.5 gr. RL33 in my 338LM Improved), but am keeping an eye on the thread.

 

[jmden]

I've not had any similar issues running 300 gr. Lapua Scenars (and I'm running 105.5 gr. RL33 in my 338LM Improved), but am keeping an eye on the thread.

Jeff, What have you noticed in terms of temp sensitivity with this powder. I'm still a little on the fence over using it. Some have had too much temp sensitivity, some report very little temp sensitivity. Not sure I can put my finger on a set of circumstances (how far off lands, etc.) where it is temp sensitive or is not temp sensitive either. I'm looking at using it in a 338 Lap Imp with 300g Bergers.

 

[JeffVN]

jmden I've not had any problems with temp swings using RL-33. I shoot my rig year round.... sort of.

But, I do not let my ammo get down to freezing (I have an ammo box trick that I use to keep it roughly 50-60 degrees in the winter), but I have shot it with ammo temps upwards of 100 degrees (but don't let it sit in direct sunlight in the desert summer).

I'm jumping my 300 gr. Scenars roughly 10 thou. Different improvement designs are all called LM Improved can make comparing any of them on an apples to apples interesting. Mine holds 121.5 gr. H2O and has a 35 degree shoulder. In my rig (31" tube) my 105.5 gr. RL-33 runs a solid 3,000 fps. FYI in my rig 100.0 gr of VV570 runs right at 3,000 fps as well. I see stated/reported loads with 338 LM Improved that are up to 109+ gr. of RL-33.

I did velocity and pressure testing from 98 gr. up to 109 gr (which was 3,100+ fps) in 1 gr. increments. 109 gr. was also showing signs of pressure with sticky bolt, flattened primers, and hint of smear. Testing was done with the rig and ammo in the shade and temps at the time were nominal (80-85 degrees). Here in the valley it rarely gets below 30-35 in the winter and summers will run 110-115+ so my main concern is heat in the summer.

I hope some of this info helps.

Jeffvn

 

[jmden]

Thanks, Jeff. I appreciate you getting back to me. I'm getting 2980 with 100g of Rebumbo and the 300 EH -.018, so I'm thinking of just staying there. Seen too many others that are having temp sensitivity issues with RL33.

 

[shedhead]

I have a 30/338lapua rogue I'm running now 106 grns rl33 230 bergs 3.70coal last year I had this same problem my speeds are consistent.so I was thinking my issue might be coming from somewhere else.I started to search and found my resizing die not resizing correctly and inconsistent.

 

[idaho elk hunter]

You are probably running over a 105% case capacity and heavily compressing the load. RETUMBO does not like that. Many say the deviation is worse than normal with Retumbo. That is true only if you are compressing the load. AGAIN Retumbo does not like compressed loads. I have seen it time and time again. I almost can bet the farm that is the problem.