IMR 4198 in 30BR

[jackieschmidt]

I just ordered 2 one pound cans of IMR 4198 from Natchez. It was in stock

I have about 16 pounds of H4198, but I am just curious to see how the IMR compares.

 

[LCazador]

Jackie case fill is different for sure and if you're a workup a load and leave it kind of guy you'll be disappointed. Of course in my opinion it's a tune and adjust game before every match regardless what powder I use. Enjoy the challenge!

 

[gunsandgunsmithing]

Yep, its bulkier and doesn't meter as well as the H powder. Haven't tested it in a long time. Not sure how it holds tune compared to the H. It might work in your long neck case but I think you'll still run out of room pretty quick with it.

 

[Bill Norris]

I just ordered 2 one pound cans of IMR 4198 from Natchez. It was in stock

I have about 16 pounds of H4198, but I am just curious to see how the IMR compares.

Let us know how it works out, please Sir.

 

[Jager]

Aye, very similar burn rate, but considerable difference in kernel density.

Here's a QuickLoad print of H4198 loaded to 104% charge density, followed by IMR-4198 loaded to the same 104%







You can get a bit more of either into the case, but IMR-4198 will never get into the same pressure/velocity range as H-4198 at comparable case fills.

LT-30 is probably a better substitute for H-4198. Here's the same 104% print for that powder...



Here's a partial powder table, when setting filters for a maximum 104% charge density AND maximum chamber pressure. Both are frequently exceeded by benchrest shooters, but it gives you an idea of how various powders stack up...

 

[jackieschmidt]

Interesting.

if the Quick Load data shows 58,700+ PSI with 33.27 grns of H4198 with the Berger 115, what do you suppose the pressure is with my 35.1 grn load behind my own 112.

 

[Jager]

Interesting.

if the Quick Load data shows 58,700+ PSI with 33.27 grns of H4198 with the Berger 115, what do you suppose the pressure is with my 35.1 grn load behind my own 112.

Jackie, the Berger 115 at 33.27/H4198 is roughly 57K psi.

Assuming your 112gr is similar in dimension to Bart's X-OUT's, your 35.1/H4198 would be something in the neighborhood of 66K psi. I think a lot of benchrest shooters are in that neighborhood.



This is using the 40.25gr case capacity (water) in my current lot of 30BR brass (converted from Lapua 6BR) and with a modest bullet jump.

 

[Larry Koch]

I just ordered 2 one pound cans of IMR 4198 from Natchez. It was in stock

I have about 16 pounds of H4198, but I am just curious to see how the IMR compares.

So Jackie have you compared the imr 4198 and h 4198 yet? And if so what’s your report.

 

[P1ZombieKiller]

@Slsspark

 

[JimPag]

I just ordered 2 one pound cans of IMR 4198 from Natchez. It was in stock

I have about 16 pounds of H4198, but I am just curious to see how the IMR compares.

Jackie. There is a guy I shoot against up here in Maine his name is Randy Butler. That's all he's been using this year is IMR 4198. He's been doing fairly well with it. I have used it at home at my range and it shoots pretty good. With my 19" drop tube I can get 35 grains in it and it is about 3/5 of the way up the neck in my std BR case. I have used 34.0 and the avg speed was 2973. 34.2 avg 2990 and 34.4 avg 3016. This was out of a 22" Rock Creek using 116 Eubers. Groups weren't too bad. I have never used it in a match though. I just have too much H4198 and N130 to take it to a match and see if it's going to work for me or not.