Help with 300 ultra groups....

[IdahoRedneck]

First let me say hello all and thank you. I have been lurking here for quite some time and the wealth of imformation has helped me a ton. I am not new to hunting znd shooting but have just got into this long range thing over the last few years.

What im trying to do is build a good huntin load that will hold sub moa groups out to 1000.

My rifle was just a model 700 sps plain janer..... I bought the sendero barrell off here,bought a B and C stock and skim beded the action. Factory trigger has been done as well.

All my brass has been match prepped..... I have heard this dont make any difference on a factory chamber but I had fun learning and doing it haha.

Load is rem brass match prepped cci 250 3.03 to ogive. Berger 210

So my question for you guys is how would you interpret this target. It was shot at 100 yards. The 91.5 grain retumbo load looks good but the vertical has me concerned..... Also the 93 grain load looks good minus the flyer but its possible i pulled it.

The two at 88.5 were foulers. The bottom right was the new 215 berger hybrid. It was 91.5 retumbo and had sticky bolts so way to hot. Im just gonna focus on the 210 for now and leave the 215 for next time.

 

[IdahoRedneck]

I forgot to give ya some important info.
91.5 averaged 3055 es of 29.
92 averaged 3072 es 33
92.5 averaged 3090 es 9
93 averaged 3095 es 33

Thanks in advance.........any tips or advive on what you guys would do with this is much appreciated.

 

[Reynolds02]

Shoot the 91.5, maybe try fed 215 primers to see if it may help lower spreads. Could also play a bit with seating depth in .005" increments to see if you can fine tune any more, but it looks good. If this doesn't help just shoot the load as it is and see how it performs further out...good luck

 

[Mikiedem]

I would increase the distance to min. 300 yards and re shoot. Also are you shooting all 3 rounds of the same load at a time then moving to the next charge? If so I would only shoot the first round of each charge, then the second round of each charge, then the last round. Marking each shot and allowing barrel to cook between shots. Takes a little more time, but well worth the info gained.

 

[IdahoRedneck]

Yes, I fired each charge weight as a group with the exception of the 4rth shot on the 91.5 grain load. That particular peice of brass was sticky in my shell holder on the press. It was the lowest shot in the group.
So move to 300 and retest all 4 charges?...... I have some 215 m primers I can test aswell. The reson for using the cci was I had much better spreads in my old load using ccis. But that was with us869 and this new barrel doesnt seem to like that stuff at all.
Its been a hell of a journey just getting this far but I can almost see light at the end of the tunnel I hope haha...

 

[Mikiedem]

I am just up the road from you in Rigby, if you want we can get together and maybe I can be some help. Finished my 300 RUM last year and have validated it out to 1532 yards.

 

[Joe King]

All 4 shoot well enough I'd do em all just like Mikieddem said, round robin style letting the barrel cool between shots. I'm betting in the end you'll go with the lowest ES

 

[meatyrem]

I was using h-1000. But I'm not finding it to be accurate. I am going to switch to retumbo. If not ill go to r-25. The best group I found with the h-1000 was around an 1.25 or worse

 

[bigeyedbass]

I hAd almost the same results switched to rl25 and cut my groups in half. ahooting a 700 bdl timmney trigger grey bull stock just had it bedded and had a wyatts extended mag installed shot a .508 3 shot group this last week going to start working on seating depth now and see if i can tighten it up more Dan

 

[Lefty7mmstw]

With these heavywieghts you all really ought to try rl50. 98 grains of it in my 300 rum pitches a 225 hornady hpbt to 2870 fps at mild pressure. 102 grains will do an honest 3000 fps in a 26" 300 rum at normal pressure. Both loads are compressed so a long box will do you good, but they will fit with a bit of work in a stock box.

 

[IdahoRedneck]

I hAd almost the same results switched to rl25 and cut my groups in half. ahooting a 700 bdl timmney trigger grey bull stock just had it bedded and had a wyatts extended mag installed shot a .508 3 shot group this last week going to start working on seating depth now and see if i can tighten it up more Dan

Re 25 had pretty much th same results as im getting w retumbo..... I thought it shot relly well in my gun but chose the retumbo because of all my reading on here Bout its temp stability.....

 

[IdahoRedneck]

I am just up the road from you in Rigby, if you want we can get together and maybe I can be some help. Finished my 300 RUM last year and have validated it out to 1532 yards.

That is very generous of ya ill pm ya and maybe I can give ya a call......

 

[IdahoRedneck]

With these heavywieghts you all really ought to try rl50. 98 grains of it in my 300 rum pitches a 225 hornady hpbt to 2870 fps at mild pressure. 102 grains will do an honest 3000 fps in a 26" 300 rum at normal pressure. Both loads are compressed so a long box will do you good, but they will fit with a bit of work in a stock box.

I was using us869...... 103.5 behind a 210 vld got me 3012 avg with no pressure signs in my gun and room for more powder..... Cant believe how dense that stuff is..... But alas I read about temp stability problems with that powder as well.....and my new barrel didnt like it.......

So I was really hopin to put somethin together w retumbo that would keep me sub moa out to 1000.... Burnt up alot of powder getting to this point. Whoever installed the brake on this barrel did not have it true and that caused me greif for quite a while til I had my gunsmith look at, figure that out, then fix it .

Was just hoping to get somebodys elses opinions on where they would go and what they would do with these groups..

Thanks again for all the replys......

 

[Mikiedem]

When I develop a long range load I will start at a distance where I plan most of shots will take place so typically my ladder will start at 500 yards with a blank piece of paper appx. 3 ft long with bull in the middle ( 1k target at army surplus works great). After deciding on my start and appx max load I will load 1 round in .3-.5 increments (depending on what I'm shooting) to my max. I dope my scope so I will hit low on the paper while holding on bull so as the charge increases the pattern will climb. Document after every shot on the target and inspect brass for excessive pressure. After all shots are fired the target will show a node with the least amount of vertical variance. Once the node is noted, it will be between .9 and 1.5 grain spread (depending on what increment I loaded) lets say the node is 92.3-93.2. Now I know that even if my powder thrower throws a little light or heavy my point of impact is going to stay relatively the same. Now I will load 3 shot loads 92.2, 92.4, 92.6, 92.8, 93.0, 93.2 and go shoot at 700 round robin style documenting each shot and find the load with the least amount of vertical variance. This will be my new best friend for this rifle. I don't worry to much about horizontal because as you know by the time you start and finish the wind here will change alot. This is what has worked for me and several rifles, maybe it will help you in your quest to 1k, maybe you already know. Figured if I didn't share then it may be new info left not shared.