Still kind of new to this forum and to the 10mm cartridge. I have been reloading for over 30yrs, but have just started reloading the 10mm. I have been searching this forum for reloading data and others places. If this has been posted forgive me like I said I'm still pretty new to this forum. I went to Accurate powder reloading data and found loads that you can match Underwood Ammo velocities and stay under the SAAMI working pressure of 37,500psi. This is with Accurate No 7. I have always loved Hodgdon Powder. Varget for rifle and Longhot for pistol. I have about 4lbs of Longhot and 2lbs of Varget. Every time I get a chance to buy either of those powder I do. I just don't understand why people are screaming LongShot when there is no loading data for it except for the 180 and 200gr bullets. I have read some Guesstimation on loads
and pressures for Longhot and they are way over pressures. I am very brand loyal but I like to know exactly what I am putting into my gun. I have found some Accurate No7 and I have a chronograph brand new matter of fact and I will be posting result of my finding on velocities and accuracy. Does anyone else use Accurate No 7? If so do you like it if not why? 

I still have some of the original pound of AA#7 I purchased back in 1990, I used some of it looking for 10mm performance.  I found it to be dirty (sooted up my guns) as compared to Blue Dot.  I still test with it on occasions.

I'll be happy to see what results you find especially in newer lots of the powder.  Do you need some data for the AA Powers?

here is some older AA data...

I will be honest, I did a quick check of some load data and found Accurate #7 to fall behind Longshot at similar published pressures:

As you correctly point out there is not any load data from Hodgdon Longshot in any bullet weights but 180 and 200, but for those two weights we see the following

Bullet Weight	|  LongShot Velocity	|  LongShot Pressure	|  #7 Velocity	|  #7 Pressure
180 gr HP	|  1,287 fps	|  34,600 psi	|  1,183 fps	|  35,300 psi
200 gr HP	|  1,172 fps	|  35,000 psi	|  1,091 fps	|  36,500 psi

On the basis of this information it seems that, at least in the heavier bullets, Longshot provides a little better velocity for a given peak pressure.  This would indicate a longer pressure curve from a slower powder, and indeed Longshot is a place or two slower on the charts than #7.

I think #7 is a fine powder for 10mm.  There is a wealth of data for it, and it produces some good results.  If you are going to stock one powder this is a great choice for versatility.

But for top velocities, Hodgdon data shows CFE Pistol to best #7 in lighter bullets and Longshot to best it in heavier ones.

Dirty I can deal with, I use to shoot a lot of unique its almost as nasty as black powder. From what I can tell did not compare side to side but the loads looks the same. The thing I like about it is that it is published data. That mean the people with all the fancy gadgets got their facts straight. Pressures are not guess work. I can watch primers and see the signs of over pressure but it is a fine line some times.

As you pointed out LongShot is a little slower burning on the Burn Rate Scale A#7 is #51 and LongShot is #53. But what I am again saying is the guys with all the right equipment published more loading data than Hodgdon.Today to I called Hodgon about publishing more data on LongShot and more bullets weights and he said there just wasn't enough interest in the 10mm cartridge. I told him there was more than they think. But unless they know like getting more calls it looks like Hodgdon is not going to publish anymore than they have now.

Quick 2 writes;

QuoteI am very brand loyal but I like to know exactly what I am putting into my gun.

That is exactly why I handload my own and hand weigh every charge on a balance beam scale...
It is also why I like doing the Pull-Downs for study purposes and documenting the history of the 10mm cartridges. 

Actually, I've been loading my 10mm using Accurate 5 for some time
It delivers over 98% of the same results of AA#7, using only only 80% of the Powder
This equals more Rounds per Pound which equals more Rounds per $$$$

Quote from: Quick 2 on September 03 2014 09:55:29 AM MDT
Still kind of new to this forum and to the 10mm cartridge. I have been reloading for over 30yrs, but have just started reloading the 10mm. I have been searching this forum for reloading data and others places. If this has been posted forgive me like I said I'm still pretty new to this forum. I went to Accurate powder reloading data and found loads that you can match Underwood Ammo velocities and stay under the SAAMI working pressure of 37,500psi. This is with Accurate No 7. I have always loved Hodgdon Powder. Varget for rifle and Longhot for pistol. I have about 4lbs of Longhot and 2lbs of Varget. Every time I get a chance to buy either of those powder I do. I just don't understand why people are screaming LongShot when there is no loading data for it except for the 180 and 200gr bullets. I have read some Guesstimation on loads
and pressures for Longhot and they are way over pressures. I am very brand loyal but I like to know exactly what I am putting into my gun. I have found some Accurate No7 and I have a chronograph brand new matter of fact and I will be posting result of my finding on velocities and accuracy. Does anyone else use Accurate No 7? If so do you like it if not why? 

I REALLY like AA7 for the 10mm but, quite honestly, I've not gone over book max with it.  I have a sneaking suspicion that it will perform CLOSE to what Longshot will do from 135-175gr bullets (esp when going OVER book data like many do with LS) but LS takes the lead with heavier bullets.  I have recently fallen in love with AA9 and I'm EXTREMELY impressed with Accurate powders in general.  I even like the smell.  A LOT.