300RUM 208 A-MAX, load,

[MT300RUM]

Well i have been wondering about the 208 A-MAX & retumbo for the 300RUM since i heard hornady came out with the 208, but haven't heard much about them for the RUM nor could i find any data for this combo, and ive asked everywhere to no avail, so i finally bit the bullet so to speak, and ordered a 100 of them, and going off old loads ive used for 210 bergers i loaded 50 rounds in 5 round 1/2 grain bumps starting at 89.5 retumbo ending w/ 94.0 grabbed the gun and went to the spot i can shoot closest to my house, but can only get out to 175yds, started off w/ 89.5 and was not impressed, until i hit 93.0 and found the sweet spot, i think i found my new combo, these groups were not shot from a bench, or even a sand bag, but off of a folded blanket on the hood of the truck at 175yds, now i don't shoot for score nor do i even know how to properly measure a group, maybe someone here can tell me what these groups would score, i shoot longrange out to 1000yds about once a week, but not for group i like to shoot plastic containers filled with colored water, it's just way more fun for me than punching holes in paper,
these are the 93.0 & 93.5 groups at 175yds, i hope this helps someone looking for the same load i was looking for..

 

[Long Time Long Ranger]

My accuracy load with the 208 and retumbo is 94 grains at 3116 fps. My best load is 106 grains of h-870 at 3228 fps. This is a 28" barrel rifle.

 

[justgoto]

Re: how to properly measure a group

How To Measure Group Size.

Then you have to figure how far you shot from to figure minute of angle.

Minute of Angle

Your shots look like about 3/4" at 175 yards, which is about .428 MOA. (If I did that right.) I always shoot from 100 yard increments so it is easier to figure.

But that looks like you have the sweet spot. Great shooting too!

 

[338 LEGEND]

My accuracy load with the 208 and retumbo is 94 grains at 3116 fps. My best load is 106 grains of h-870 at 3228 fps. This is a 28" barrel rifle.

That h-870 is goooood stuff, but im getting low, down to around 6lbs.

 

[Booney]

What primers are you loading with.

 

[Long Time Long Ranger]

I use federal 215 match primers on all my big guns.

 

[MT300RUM]

Well i would have to say this load works for me, after shooting the 93.0 & 93.5 RETUMBO w/ the 208 A-MAXs, i split the dif and went with 93.3, and loaded up 50 in new weight sorted nosler custom brass, and went to the place i shoot long range, we set targets at 300 400 500 600 700 800 900 1000 1200 yds for MOA adjustment data, all targets were large carboard with 8" peel and stick blaze orange, except for the 1200yd it was a full culligan water bottle with the peel and stick, after getting all my elevation data out to 1000yds worked out, all that was left was the jug at 1200yds i dialed in 24.7 moa and let one go, elevation was perfect but my windage was off to the right side i dialed in for a 10 mile an hour wind and then this happened, i know luck played it's part too, but after seeing what this load did at all the other yardages, i wasn't all that shocked, this was the longest shot i have ever taken in my life, and after watching that jug explode at 1200 i'm hooked, the shot measured 1.221 from center of bull,

 

[Gone Ballistic]

Well i would have to say this load works for me, after shooting the 93.0 & 93.5 RETUMBO w/ the 208 A-MAXs, i split the dif and went with 93.3, and loaded up 50 in new weight sorted nosler custom brass, and went to the place i shoot long range, we set targets at 300 400 500 600 700 800 900 1000 1200 yds for MOA adjustment data, all targets were large carboard with 8" peel and stick blaze orange, except for the 1200yd it was a full culligan water bottle with the peel and stick, after getting all my elevation data out to 1000yds worked out, all that was left was the jug at 1200yds i dialed in 24.7 moa and let one go, elevation was perfect but my windage was off to the right side i dialed in for a 10 mile an hour wind and then this happened, i know luck played it's part too, but after seeing what this load did at all the other yardages, i wasn't all that shocked, this was the longest shot i have ever taken in my life, and after watching that jug explode at 1200 i'm hooked, the shot measured 1.221 from center of bull,

What depth are you seating your bullet? I tried this load seated 2 thousands back from my L&gs and experienced some serious pressure problerm. They chrono graphed at 3284 avg. 30" barrel and grouped 3/4" which isn't anything special. I don't know whether to back them off another couple of thousands or seat them at 3.6" coal which is listed as the SAAMI coal in my books. Can you give me any help here?

 

[smoked]

im heading into the reloading room to start a new load, i have 200-208amax's 1lb of retumbo,1lb rl-22,and 1lb rl-25 with win non mag,cci br,fed 215 match,and cci mag primers with rem brass, first load will be 92.5 gr retumbo cci250 and not sure what my length will be yet, then i will go chrono it and see what happens. i will bump up .5 gr to 94, rifle is a stock sendero rum with the xmark pro brick trigger.

 

[Gone Ballistic]

Smoked,
Let us know how your loads turn out. I shot some .208 A MAX's the other day that I backed off the lands 2K and had pressure problems from 91.5gr. on up to 93.5 with Retumbo. I have backed some off another 2K to 4K and some to 5K to see if that was my problem. When I've shot the same loads at SAAMI length of 3.6" I've not had any pressure problems loading up to 94.2 with Retumbo. I just haven't been able to get close to the groups I get with 200 gr Accubonds with Retumbo at 95.2 gr., 3246fps average at 10 ft. on the chrono. I'm shooting a custom on a 700 Rem action with a 30" Lother Walther barrel.

 

[smoked]

well i started at 92 and the absolute longest that will fit in the mag and half *** feed is 3.670 length which will be important as it will be a hunting rifle, the first run will be one shot each through the chrono 92,92.5,93,93.5,and 94 this is just to get the feel for the round, i am a bit nervous as i dont usually jump more than .2 of a grain as i go up. i will be wearing glasses,plugs,muffs,and a heavy jacket too i am looking for 3050-3100 fps.

 

[Gone Ballistic]

I had a 4" magazine put in my custom to accomodate longer bullets, like VLD's. I had the 208's set at 3.874 the first time. I have backed them off to 3.871 but haven't tried them yet. I'm going to load some at 3.750 jut to see if there's much difference in group tightness. On the Accubonds I set them at 3.873 and shot .228-.317 MOA 5 shot groups at 100 yards. The best groups I got with th A-Max was .799MOA

 

[smoked]

I had a 4" magazine put in my custom to accomodate longer bullets, like VLD's. I had the 208's set at 3.874 the first time. I have backed them off to 3.871 but haven't tried them yet. I'm going to load some at 3.750 jut to see if there's much difference in group tightness. On the Accubonds I set them at 3.873 and shot .228-.317 MOA 5 shot groups at 100 yards. The best groups I got with th A-Max was .799MOA

i was playing around with one at 3.8 and it left no marks on the bullet and bolt closed easily, i might have two different loads, one might have to be a single shot, i want to try the 200ab also,

 

[smoked]

i went out and shot a few, my chrono just reads error 1 but its cloudy and kind of dark so i shot the 92,92.5,and 93, with no pressure singns or funny smells at all, maybe the sun will shine tomorow looks like 94 gr retumbo wont be too much at all at 3.670 length in the sendero, all shots were smooth and recoil felt good and not out of hand.