Varget versus IMR4895 in LMT MWSE 308 semiauto?

[JimGnitecki]

I have been ladder testing IMR 4895 (NOT H4895) in my LMT MWSE 308 semi auto, using Lapua cases, Winchester Large Rifle primers, and Sierra 175g Matchking. Results have been good.

But I see so many on this forum and elsewhere using Varget instead. I see from the powder burn rate tables that Varget burns slower. In addition, the Hodgdon 2012 Annual Manual shows that the peak pressure at max loads is lower with Varget than with IMR 4895 (48,600 CUP versus 57,800 psi), but since one was measured with copper plugs and the other via transducer, I don't know if the actual pressure (measured using the same method) would be different or not.

I also seee an unbelievable difference in maximum powder charges, between the info in the Hodgdon manual and the info in the Sierra manual. The Hodgdon max charges are WAY higher. Since Hodgdon makes the powders and did use the Sierra bullets for the testing, and Sierra does not make the powders, it is tempting to assume that the Hodgdon data is the one to believe.

I am interested in what changes might occur in:

- Accuracy?
- Attainable ACCURATE velocity?
- Cleanliness?
- Gas port pressure higher or lower?

My priorities are:
1. Being easy on the firearm
2. Accuracy
3. Cleanliness

Peak velocity is not a priority, as I want to maximize case life.

How would results using Varget versus IMR 4895 LIKELY differ?

What is an actually good starting point and maximum charge for the Varget in a typical 308 semi auto AR rifle?

I would really have liked to try a Vihtavuori powder, since I have had such great experience with VV powder in my handguns, but I can't get any VV rifle powder locally, and would have to pay the hazardous shipping fee TWICE (once for 1 or 2 pounds to "try" and then again on an 8 lb container if I like it, so I have pretty much given up on that idea.

Jim G

 

[mrhog]

Re: Varget versus IMR4895 in LMT MWSE 308 semiauto?

I used varget in my armalite sass until i tried IMR 4895. The IMR is a faster burning powder and seems to work well in the gas guns. Rite now I'm useing 44 grs. of 4895. some seem to think that this is a hot load. My loading data says 45 is the max load.I haven't made up my mind if i'm going to use this load or not; but for now it looks good. I still have more testing to see if this will work out or not.

 

[375rgr]

Re: Varget versus IMR4895 in LMT MWSE 308 semiauto?

Varget is going going to be more temp. stable it will have alot lower deviation on MV over a changes in temp. Accuarcy from my exp. has been better with Varget. VV powders have huge swings in velocity with tempurature changes. Stick with hogdon's reccomendations on start and max. If you wait to see signs of pressure on the case you are alot higher than you think when they show up. I have won alot of matches with Varget in a bolt gun the accuaracy was outstanding. It was alaways close to the established base line elevations on the scope better than any other load for .308

 

[BCP]

Re: Varget versus IMR4895 in LMT MWSE 308 semiauto?

People use varget because it is temp stable. 4895 you'll probably have to drop a grain or two for summertime.

 

[mkollman74]

Re: Varget versus IMR4895 in LMT MWSE 308 semiauto?

Check out ARComp...

 

[JimGnitecki]

Re: Varget versus IMR4895 in LMT MWSE 308 semiauto?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mkollman74</div><div class="ubbcode-body">Check out ARComp... </div></div>

????

Jim G

 

[Rhyno430]

Re: Varget versus IMR4895 in LMT MWSE 308 semiauto?

Imr 4895 and h4895, from what I have read is what a lot of people used before varget.

While varget is better than either, both are pretty good as far as temperature properties, and muzzle velocity variations.

I use it in my auto 30-06, 46.5 grains of h4895. Gave me uniform ejection, and right at moa accuracy, which for my brush gun is good. That was a really light load and never pushed it passed that since it was that accurate.

Try it out, it'll be easier on the internals of the rifle to. I'm actually going to try it in my ar15 and if I get good results ill keep using it instead of benchmark so I only have to stock one powder. Then i'll try it in my .308 when I get around to buying that.

 

[Rhyno430]

Re: Varget versus IMR4895 in LMT MWSE 308 semiauto?

Oh, I forgot to mention as well.

You can use 4895 in reduced loads for young kids and females that are sensitive to kick.