Home Forums Hunting & Shooting Ask The Gunwriters MD Are MRP and RL22 Exactly the Same?

Powder Valley didn't even list primers when I visited the site last night. I don't think the retailers are conveying whether the components are still made, just that they won't be available for a significant time.

Yeah, you may slip up on a can of powder every now and then. But you better pull the trigger quick, because it's not likely to be there when you check back.

Forget primers....

DF

I grabbed some online a couple weeks ago, and some locally. They didn't have the Varget/IMR4266 I want, so still must keep looking. Missed the boat on primers though. My brother bought some in November locally, got a few thousand. Those are the last I've heard of anyone buying any. Whenever I go into local businesses, they act like they've never heard of 'em: "Primers? What? No. No."

Yeah, whatever physical & appearance differences I've seen have not seemed to matter & like you, I just used them interchangeably over the years, mainly in 270's & 280's of which I have multiples in each caliber, & also in several 7 Mags & 338 Mags.

I always end up with the virtually same velocities from both & the same max loads in a given gun.

So, I dunno if they are different or not, & it really doesn't matter anymore, but as I said in the earlier post, the performance is the same & I've tested them both enough to feel OK using the same charges of either so I treat them as if they are the same. I've never seen any real spikes in the lots I've used either. I've always bought quite a bit at one time, so my number of lots vs the amount used is probably lower than many others.

And that encompasses RL-22 from when it 1st came out & MRP for the same rough time period up until now.....so for me, that time period would have started in the late 88-'89 until now. I have both powders in their old packaging, & both powders in their new packaging. I cannot recall what year MRP was introduced but I think it was in the mid-70's; RL-22 & 19 were introduced in 1988 & I stared using them all around that time.

MM

Sounds about right as MRP was brought out when they stopped making N205.

What happened to MRP2? It hasn't been replaced by another similar powder as far as I know. Is MRP2 the same as R25?

I started using MRP in 7mm Weatherby just wanting to try other powders and found that it produced excellent consistency in velocity and accuracy before I was aware of the RL22 kinship. 72.0 gr of MRP behind a 150 TTSX gets the job done! I have several pounds from the same lot # so I’m not working up other loads with it out of conservation. I put my .300 Weatherby on a RL26 diet. Happy Trails

They may be similar, but not the same. I use both powders for two 300 Win. I wish they were interchangeable but they're not. One rifle shoots MRP into one hole, the other RL 22 into one hole. Swap the powders and groups open up. Luckily I've got several poounds of each.

Dunno what replaced MRP2- had a bunch of that but traded it for 217.

Even lot-to-lot variations in the same powder can have that effect. That doesn't necessarily prove that they are not the same.

I have never experienced temperature sensitivity in MRP, both in my reloads and factory Weatherby ammunition. I have no experience with Reloader22.
NWT

The thing to remember about powders is that each kernel is probably different from the next kernel, not to mention that the fact that from day to day, each kernel is different from what it was yesterday, due to such factors as greater age, differing humidity and other meteorological conditions, the phase of the moon, and whether or not it got a good night's sleep. Given this, a load that was acceptable yesterday should probably be reduced 10% today and worked up as (unreliable) signs indicate.

And then we have RL-23 thrown into this mix.

Ever think about going in to politics?

No. Do you believe my answer is "equivocating"?

What I have always done in my writing is report what happened during my testing, and also report what various companies claim, though. I majored in biology in college, so know something about testing various factors. Also have been a full-time professional journalist for 38 years now, and not just in gun writing. Long ago learned to avoid making blanket statements, especially years later based on evidence only available at the time.

Just bustin your chops.

I suspected that might be the case!

Thanks MD and others for bringing this to light. May pick some up instead of R22 should supplies return some day.

All I can tell you is this: In every caliber that uses either MRP or RL-22, the results with the same load have been exactly the same.
257 Weatherby
7mm Weatherby
300 Weatherby
340Weatherby