IMR 8208 XBR

[rkaires]

Looking for some feedback on IMR8208XBR for .308 and .223.

Thanks,
Bob

From IMR website:

IMR 8208 XBR The latest in the versatile IMR line of fine propellants, this accurate metering, super short grained extruded rifle powder was designed expressly for match, varmint, and AR sniper cartridges. Ideally suited for cartridges like the 223 Remington/5.56mm, 308 Winchester/7.62mm NATO and the 6mm PPC, shooters will find IMR 8208 XBR totally insensitive to changes in temperature, while yielding max velocities and “tack driving” accuracy. Clearly, the competitor’s “choice” and the Varmint Hunter’s “dream powder”.

 

[turbo54]

Re: IMR 8208 XBR

I didn't find it to be the "wonder powder" its hyped to be.

It was accurate.

It metered pretty well - better than Varget but not amazing.

It was slow. 100fps less than Varget with 175smk.

 

[biner626]

Re: IMR 8208 XBR

2774fps 77SMK in my .223. I can't say for temp stability. It does meter well.
ETA This velocity was from a 18" 1:7 gas gun

 

[JBomb]

Re: IMR 8208 XBR

I concur with Turbo and biner, although it meters well...I couldn't get the same velocity as varget in a 308. There was also pretty big swings in velocity over 0.5 grain increments.

Hope this helps.

Kind regards,
Jared

 

[bward]

Re: IMR 8208 XBR

It will give you better velocities than varget with 155's in a 308, this is due to its faster burn rate. When you get to 175's and heavier, 8208 is a little to fast and varget outperforms it.

 

[Hedge]

Re: IMR 8208 XBR

I'm thinking it's a better small case powder. Shoots 100 - 200 fps faster than H4895 in my .204R. Very good accuracy from it.

 

[holdoff]

Re: IMR 8208 XBR

Burn rate is very close to IMR 3031. It is not the powder to use with the heavy bullets is .308 WIN. Varget/RE-15 is the way to go.

However, 8208 works with the 155gr bullets very well. Velocity gain is apparent, but the SD/ES is really impressive. The charge ranges are wider for a given node and that lends itself to throwing charges with acceptable numbers.

I am using this powder exclusively for .308 Win F/TR loads with 155s.

Also, this powder does work well in .223 REM. Seems that IMRs powder charge data is a bit conservative. I have found you can push that a bit.

At the limit this powder peaks in pressure very quickly.

 

[turbo54]

Re: IMR 8208 XBR

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JBomb</div><div class="ubbcode-body">I concur with Turbo and biner, although it meters well...I couldn't get the same velocity as varget in a 308. There was also pretty big swings in velocity over 0.5 grain increments.

Hope this helps.

Kind regards,
Jared
</div></div>

When I chrono'd ladders, there was a very linear correlation between charge and velocity....until I hit max! That last .25gr was enough to increase velocity 70fps, but the cases showed pressure.

 

[rkaires]

Re: IMR 8208 XBR

Thanks for the feedback guy's. I've gotten good performance form IMR4064 and Varget in my .308 but not so great in .223. AA2520 worked best for me in my .223. My hope is to find a powder that preforms great in both.

 

[rkaires]

Re: IMR 8208 XBR

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: holdoff</div><div class="ubbcode-body">Burn rate is very close to IMR 3031. It is not the powder to use with the heavy bullets is .308 WIN. Varget/RE-15 is the way to go.

However, 8208 works with the 155gr bullets very well. Velocity gain is apparent, but the SD/ES is really impressive. The charge ranges are wider for a given node and that lends itself to throwing charges with acceptable numbers.

I am using this powder exclusively for .308 Win F/TR loads with 155s.

Also, this powder does work well in .223 REM. Seems that IMRs powder charge data is a bit conservative. I have found you can push that a bit.

At the limit this powder peaks in pressure very quickly. </div></div>

Sounds like I need to give 155gr smk's a try. I been shooting 175's for a while now out to 800yds. If 8208 works as well with 77gr smk's I think I found my next powder.

Thanks,

 

[holdoff]

Re: IMR 8208 XBR

Hey all. One very important thing that I failed to mention regarding 8208 with 155s in 308 Win.

The max charge from IMR is listed at 45.3 grains. This charge was very hot and probably over max pressure by a wide margin. I am shooting a factory Savage Palma with a 30in barrel. I pierced primers just beyond this max charge doing a OCW during load development, and experienced hard bolt lift and heavy ejector wipes with book max.

This was also seen in this article from accurate shooter/6mmbr website.

http://bulletin.accurateshooter.com/2010/03/imr-8208-xbr-performs-well-in-308-win-testing/

Read this article, and the warning at the bottom. The top for me seems right at 44.0-44.2gr. I have about 20 once fired lapua cases that have loose primer pockets after one firing with the book max load.

 

[bward]

Re: IMR 8208 XBR

I must have a very slow lot of 8208. I didn't hit pressure with the 155's in my AW until 47.4. I ran quite a few rounds down it with 47.0 grains at 2925 fps with no issues.

 

[JBomb]

Re: IMR 8208 XBR

I'm not sure if it could just be me, but it seems like 8208 has a sharper recoil than varget. Maybe, its me, but varget seemed " softer" recoiling.

I have some 155 Lapua Scenars loaded up now with XBR and Varget, once I get to the range I'll post the difference.

Kind regards,
Jared

 

[223ai]

Re: IMR 8208 XBR

46.0 got me 2890 with 2156 palma smk's out of a 20" Rock with a 95 palma chamber. 45.6 has the same bullet at 2925-ish out of a 24" Bartlein. It's a great powder for the 155 class of bullets.

 

[gcoulsey]

Re: IMR 8208 XBR

I started a load for Berger 70vld's in a factory Steyr aug,
(20" 1/9 twist chrome lined)
But couldn't get over 2700fps with Varget..
8208 xbr is getting me 2830fps with no pressure @24.7grns
Which is quite a bit over book max, seated to mag length 2.26"COAL

I havnt fine tuned the load yet, but it's about .75MOA bipod/rear bag.
I have read the nodes are a bit tighter with xbr than Varget, and that agrees with
My tests so far.. ES numbers don't seem as tight either.. But still a bit more work to do on the load..

 

[rkaires]

Re: IMR 8208 XBR

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gfunkUK</div><div class="ubbcode-body">I started a load for Berger 70vld's in a factory Steyr aug,
(20" 1/9 twist chrome lined)
But couldn't get over 2700fps with Varget..
8208 xbr is getting me 2830fps with no pressure @24.7grns
Which is quite a bit over book max, seated to mag length 2.26"COAL

I havnt fine tuned the load yet, but it's about .75MOA bipod/rear bag.
I have read the nodes are a bit tighter with xbr than Varget, and that agrees with
My tests so far.. ES numbers don't seem as tight either.. But still a bit more work to do on the load.. </div></div>

That's encouraging data for the 70gr Bergers. Have you tried 8208 in your .308 yet?

Thanks,

 

[5R Milspec]

Re: IMR 8208 XBR

I went all the way to 24.5gn useing a 69gn NCC. ( 223 )the 24.5gn load showed to much pressure for me.so I kept the 24.0gn load that runs in around 3000 fps in my rifel.my C.O.A.L. is long and just into the lands at 2.290 with Lapua brass.I think if I went with win brass I could get a little more in the case.but I see no reason to do such a thing.the load just shoots to good for me to change anything.

yes,its good for any temp.I have shoot the load above at many temps with no change at all.from 34-95 and up temps.

have not used it in a 308 yet.my Varget loads are just fine for me.so I see no reason to test it in a 308 yet.you know if its not broke there is no reason to fix it.

 

[shoot4fun]

Re: IMR 8208 XBR

8208XBR shoots extremely well in my 6BR long range BR rifle with the 107 SMK.
My attempt to get good loads with the 6PPC short range gun were not as fruitful. I got all the signs that it just doesn't like temp swings or, even more so, fair changes in humidity. As humidity dropped during a shooting session the accuracy did too.
I was disappointed with velocity in my 223 with the 77 SMK. AA2520 solved that problem.
I have a very good load in 308 and will not leave Varget there.

 

[shoot4fun]

Re: IMR 8208 XBR

Here is the link to the OCW I ran on my 223:

http://www.snipershide.com/forum/ubbthre...982#Post3008982

 

[gcoulsey]

Re: IMR 8208 XBR

Nope I havnt tried it in .308, I shoot heavy bullets with Varget or vihtn550
So Im happy with those loads

I tried the xbr in the .223 because Varget was filling the case (lapua) and crunching ALOT without pressure signs so I switched to the faster xbr.. Worked for me!
NOTE I'm loading to mag length, so am a bit shorter on case capacity than others
Seating out near the lands

Btw.. These 70vlds shoot very well at mag length, and I'm sure in a better setup than my AUG (horrible trigger etc..) I'm sure the groups would be much tighter than I'm achieving at the moment!!!

 

[YAOG]

Re: IMR 8208 XBR

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">I didn't find it to be the "wonder powder" its hyped to be.

It was accurate.

It metered pretty well - better than Varget but not amazing.

It was slow. 100fps less than Varget with 175smk. </div></div>

I ran out of case capacity and started to show pressure signs with only moderate loads of Varget with long bullets like Hornady 178g Match bullets. Common Varget loads I tried were about 5% compressed even with Sierra 175g SMKs.

With XBR I had none of these issues with 175g SMK or 178g Hornady match bullets with velocities within 10fps max. Varget loads. XBR seems to be pretty temperature consistent at least here in SoCal shooting mid 50F to low 100F air temps.

I don't use a powder measure, I scale my charges with a funnel which seems to produce a slight loss in capacity.

 

[rkaires]

Re: IMR 8208 XBR

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">I didn't find it to be the "wonder powder" its hyped to be.

It was accurate.

It metered pretty well - better than Varget but not amazing.

It was slow. 100fps less than Varget with 175smk. </div></div>

I ran out of case capacity and started to show pressure signs with only moderate loads of Varget with long bullets like Hornady 178g Match bullets. Common Varget loads I tried were about 5% compressed even with Sierra 175g SMKs.

With XBR I had none of these issues with 175g SMK or 178g Hornady match bullets with velocities within 10fps max. Varget loads. XBR seems to be pretty temperature consistent at least here in SoCal shooting mid 50F to low 100F air temps.

I don't use a powder measure, I scale my charges with a funnel which seems to produce a slight loss in capacity.

</div></div>

How do you find accuracy with XBR compared to Varget?

 

[rowrd]

Re: IMR 8208 XBR

Using an 18 inch 7.62 OBR...

I've been working with 41.5 grs 8208 / 168 Nosler Custom Comps in Winchester brass and 42.0 grs Varget/ 175 Sierras in same brass..

Don't know the velocities are, but I'm sure they're slow. I was looking for a consistent and accurate load at the lower end of the node.

The Varget load has turned out some occasional incredible groups, while the 8202 load comes close but overall consistently smaller over 10 five shot groups. The CBS with 8208 is not any different than the rest of the group.