RL-22 and MRP.........the same? Ok. Help me understand.

[350JR]

I keep seeing over and over that RL-22 and Norma MRP are identical powders.

But......

I ALSO keep reading QL data print outs with both on the list for the cartridge........and they are NOT side by side and normally, not even close together like 414 and 760 almost always are.

QL states it's main purpose is to compare powders and charges so.......something just doesn't click when doing that and trying to consider those two powders being "the same".

Burn rates show them together. VMD (density) is the same or VERY slightly different.........but on QL data? Nope.

What am I missing?

God Bless
Steve

 

[Ridgerunner665]

They are the same... And as such, they share the quite large lot to lot variations and temperature sensitivities.

In my opinion... Reloder 26 can do anything 22 or MRP can do, and do it better.

 

[350JR]

I agree with all that but does not the same apply to 414 and 760 as far as lot to lot changes?

Evidently whatever volumes were input into QL has MRP denser going by what I've seen with the same percentage of fill showing a bit more powder in MRP vs RL22.......and, so far, all I've seen show MRP always faster.....but not by much most times.

I've also notice that if the fill percentage is lowered, the results between the two gets more pronounced. 112% can put them kinda close, but at 105% it separates them by a dozen or more (up to 20) other powders.

Thanks
Just curious if this is a QL snafu or what is all.

I like RL26 info enough to buy a bottle myself for heavier bullets.
Thanks again
God Bless
Steve

 

[AK7AN]

For the cartridges I reload, 270W, and 257 Roberts, QL shows quite a bit of difference between RL22 and MRP. It also shows for both that with heavy bullets RL26 as top velocity with MRP 2nd, with negligible difference in Velocity, usually less that 30 FPS.. So for what I use... I would say that there is a difference between RL22 and MRP. RL 22 hits the list like 350JR said, quite a ways down with less velocity. Maybe it just depends on the cartridge and load density..
I use MRP and have had excellent results..
Take care
Ed

 

[Math Teacher]

I think you will find that RL23 more nearly duplicates RL22 while giving the benefits of RL26 which is slower and more like RL25.

 

[350JR]

One email from Ramshot (who handles a whole pile of "brands", including Norma) and also from Alliant.

Both say they are not the same powder. Ramshot says MRP is "slightly faster and is a different density"

Alliant said they are " Different propellants and need to use the proper load data developed for the components being used." but no details and why I asked about the VMD.

They gave me 0.92 GRAMS per CC. (trying to find a conversion. hey.....is 4AM here lol)
But wow..........that doesn't seem possible in my sleep deprived brain. A gram is like more than 15 times what a grain is in weight. Sorry if I'm missing something.

That is weight per cc. I should have asked for the "VMD" not density. That comes out .0704 for VMD for RL-22 but don't quote me on it. I'll find out.

The reason I started this is due to the last QL I had run for me.
Both MRP are listed at 105% (the upper limit asked for)

Norma MRP 105.0 55.2gr

Alliant Reloder-22 105.0 53.5gr (20 powders down and 86fps slower and a slightly lower pressure.)

It just had me scratching my head since I ASSUME VMD and burn rates are constants in QL for powders.

Not being argumentative. Just trying to get data from the companies verifying the difference.

More later.

God Bless
Steve

 

[350JR]

Just passing along info gotten from both sources.

Alliant said "The VMD of RL22 (Volume Mass Density that which Lee uses) is 0.072."

Ramshot said "The VMD of MRP is .070"

Both said MRP was "slightly faster".

Old info I had on RL22 gave a VMD of .0697. I still take "tech information" with a grain of salt.

I had a Speer tech tell me that ALL Speer's boat tail soft point were not hunting bullets and only for target.

Just info as I got it.........right or wrong.
God Bless
Steve