Working Load for 7mm RM not working for me...

[Nandy]

I am having a terrible time working a load for this rifle. I am over 50 rounds (50 were done with a loose scope, not counting those) and I am not close to consistently shooting sub moa. The primary use for this rifle is hunting and for that purpose up to 200 yads is ok but I expect more of this gun. I reloaded in the past for a 30-06 with an A&B sporter barrel and I would shoot sub moa all day so why not with this custom barrel... Here is the gear I am using:
The gun:
110 Action- SSS Timed and Trued
SAV-2
Choate Varmint Stock - Skim bedded, tang and barrel floated.
Aftermarket Recoil lug (similar to SSS)
Brux (SSS) 7MM RM, 1-9, 26", Varmint Barrel, SSS Brake (installed into action by SSS)
Warne 1-Piece Tactical Picatinny-Style Steel Scope Base
Leupold 30mm QRW Quick-Release Weaver-Style Rings
VX III 50 MM 4.5x10 Leupold Scope
Base screws are not touching the barrel. I measured in 2 different ways and it is not possible. Torque to 25 in/lbs.
Ring screws are torque to 28 in/lbs.
Action screws are torque to 30 in/lbs.
All above screws were double checked to day and would not turned when I tried the above torques.

All above hardware was in use and assembled in similar fashion while the rifle had the 30-06 barrel, for except of the new barrel (of course) and the skim bedding work.
Gun has been cleaned always using a Possum Hollow Bore Guide and a Nylon Coated Dewey 1-Piece Cleaning Rod 27 to 34 Caliber. Even thought it is a hand lapped barrel I still shot and cleaned it once after every shot for the first 10 shots.

Shooting gear:
Shooting of Sturdy wood bench.
ProChrono
Caldwell Rock Front Shooting Rest
Rear shooting bag similar to "Hyskore Front Shooting Rest Bag"


reloading gear:
Lee Neck Collect Die
Forster Ultra Micrometer Seater Die
140 grain Accubond
winchester brass
cci-250 primer
rl-22 powder
RCBS RangeMaster 750 Electronic Powder Scale

Reloading method:
Im reloading the same way as I do for the 30-06. One thing I notice is that I used to have a lot of duplicate speeds. I dont recall the sd and es exactly but they were under 20. Not so much on for this 7mm and there is where I think my problem is but allow me to continue.
All Brass is now fire-formed. Primer pocket and hole gets cleaned.
Max OAL is 2.756 and I am loading .01 shorter at 2.746. The OAL was measured with the Hornady Lock-N-Load Overall Length Gage and using my caliper with the Hornady Lock-N-Load Bullet Comparator. all my loads are .001+- from the 2.746. Bullets are sorted by weight and I use the same weight for all bullet to test groups.


All shots at 200 yds:

First attempt:
Brass were not fire-formed at this time.
Ignore the center target. It was there just for me to make sure I was in paper. The lower 2 shots on that target where shot at target 7.



Date: 9/11/2012
Caliber: 7mm RM
Bullet: Accubond
Grains: 140
200 Yds

String-----Gr.----Grp Size----Std Dev---Ext Spread-----Hi Vel-----Low Vel---Ave Vel----Sht 1------Sht 2------Sht 3
1---------66.5---1.343----------24-------47----------3003------2956------2976------3003------2969------2956
2---------66.8---3.213----------21-------40----------2989------2949------2973------2949------2989------2982
3---------67.1---2.817----------20-------34----------3030------2996------3019------2996------3030------3030
4---------67.4---2.245----------35-------49----------3065------3016------3041------3016------****-----3065
5---------67.7---2.746----------12-------21----------3065------3044------3051------3065------3044------3044
6---------68-----0.547----------20-------35----------3058------3023------3046------3023------3058------3058
7---------68.3---3.556----------25-------49----------3093------3044------3072------3044------3093------3079
8---------68.6---4.137----------17-------29----------3122------3093------3112 ------3093------3122------3122

I would shoot the first cartridge for each load at the pertaining target. Meaning I shot all the loads in the column "shot 1" then the next column and so on.
My best 2 groups are 6 and 4 (if I ignore that high shot). I did have a problem were I forgot to change the string number for the last set of shots and to make it worst the chrono missed one shot. I know my the "shot 1" column is correct so I looked at the numbers and determined that shot 4 on column "shot 2" is probably the one that was missing.





Second Attempt:

Brass fire-formed.
All shot at 200 yds.
String-----Gr.----Grp Size----Std Dev---Ext Spread-----Hi Vel-----Low Vel---Ave Vel----Sht 1------Sht 2------Sht 3
1---------67.9---1.39----------07-------14----------2996------2982------2989------2989------2982------2996
2---------68.0---2.66----------26-------50----------3108------3058------3086------3093------3058------3108
3---------68.1---2.03----------13-------23----------3197------3174------3189------3197------3197------3174

So in my second attempt I was trying to duplicate the loads and hopefully the results... Not quite so... Not sure if it is because the brass was fire-formed but this was the way I developed the load for the 06 with no much difference. I can see looking at my mean velocity (ave vel) where the speed is all over the place.



What makes it worst is that I ran out of rl-22 for that lot and the 2 pounds I have now are not the same lot as the 1 lbs bottle I finished. but these 2 1lbs bottles are from the same lot. So I am expecting this numbers to change once again...

Let me know what y'all think. I have 25 loads with 160 accubonds that I have not tried but I am running out of time for deer season and not sure if I want to invest more time on the 160 gr...
Thanks!

[wbm]

I would switch to IMR4831 or H4831.

[WV338]

I shoot 162 gr A-Max over 59 grs of IMR-4350. Shoots one ragged hole with a 26" heavy barrel.
Good luck and good shooting...

[BigHorn]

Looks like the groups I have gotten with Accubonds. Seem to be a very in-consistent bullet. When they first where released they where the rage and I test a bunch of sizes in Customers rifles. None shot well.
Can't help you much with data as I have always viewed the 7mag as a "160gr" cartridge and you seem to be leaning towards 140's
My go-to test load is;
168gr Berger vld hunting
70.5 grs H1000
CCI-250

Being a non-liker (hater) of Leupold scopes I would ask if you have proven the scope to be accurate ???

[Nandy]

It was working fine when this action had a 3006 barrel. I know something could have happen and now it could be broke but I would have to switch this back to 06 to prove that. Not something I want to do now. I will probably try a different powder, that's my inclination right now. I might shoot those 160 as they are before getting new powder.
Why are you a Leupold hater?

[BigHorn]

"Why are you a Leupold hater?"
Because of several hundred ??? performance geared rifles I have seen more of them fail than all other "Quality" scopes combine. Not tracking well is a big problem, but just not being accurate is as well. Meaning a new assembled custom rifle, gear towards 1/2moa standards shooting 1 1/2 or so. Round groups but not very tight ones. Wonder around with some load tuning to no avail, swap out with a known "accurate" scope and the rifle is a 1/2" performer with most any sane load. This very common, in my experience. Your groups look to be possibly scope related, longer strings of one set load will bare out whether it is a wander or not.

No worries there will be a dozen posters on here next telling you how they have never had a problem with a Leupold, blah, blah, blah..........best warranty in the industry....etc....

IMNTBHO I am thinking you are handicapping yourself with the Accubond and a Leupold.

[Nandy]

So no one thinks the numbers from the chronograph might indicate a problem?

[stomp442]

I too have never had good luck with nosler Bullets. Try a sierra game king and see how it does. I have always said if the bullets in the green box don't shoot you got a problem. Also play with seating depth and see if that helps anything.

[BigHorn]

So no one thinks the numbers from the chronograph might indicate a problem?

No. Not at 200, 2 of all those 3 shot groups are near 1/2moa. You got a flyer problem. Bullet, scope, or shooter

[Nandy]

No. Not at 200, 2 of all those 3 shot groups are near 1/2moa. You got a flyer problem. Bullet, scope, or shooter

So I dont need that new scale?!... Dang you Bighorn! lol (just kidding, hope I dont offend you). I will pursue the scope issue. I think I have 2 other scopes somewhere in the bottom of that gun case. If not I will try to get one that will not break the bank or at least I can return if it dont cure the problem...

Thanks everyone for your help. If anyone has anything else to add please do so.

[BigHorn]

Not offended, no worries.
Accuracy questions/answers are always a basket of snakes to deal with. We (commentors to the thread, usually have no idea of the variables)
Sometimes the shooter has a crap rifle, crap ammo and a crap scope along with no skill shooting, in high gusts off of the tailgate .......... tough to give advise with that :):):):)

I might try a handful of load #6 and fire a couple of groups. Keep a record of which shoots are going where (i.e. shots 1 &2 are 1/2" apart, 3&4 are 2" away, shot 5 is between 1&2....that kinda stuff.) ..... might be easier than swap scopes for you.

Sorry to say in our hi-tech world, I am not a LadderLoading guy, rarely use a chrony, don't load in 1/10th grain step ups, .001" seating depth step ups.....etc....... I normally start with a good know accurate load, a rarely venture far.
But I also never even bother to pull the trigger unless I know the scope is perfect, using known near perfect ammo I have loaded, the rifle is tuned to shoot, shooting conditions are right ...... I am old enough and cynical enough just not to bother with all things not be as right as I can make before any testing.

All that said if it was brought to me with a complaint, I would remove the scope, install a Zeiss I have here I know is perfect, check and scrub the bore, look over the rifle with a thought towards peak performance (trigger, bore, bedding, crown, chamber, throat etc...) and with yours being a 7RM, I would take a few new/pretty WW or Nosler new cases, prep them, seat cci-250's, fill with 70.5 H1000 and seat a 168berger/162AMAX/168LRX kissing the lands and see what it does. I don't use any bonded, accu, moly-ed, seconds, blems, sst-ed, ultra-ed....etc........ pretty much stay with the basics all the way around and normally shoot little groups

[Nandy]

Today we looked a lot better:



Chrony numbers were also better.

Once I was done shotting I had a chance to talk to one of the guys that do competition shooting and he also agreed to change to Berger 160 VLD Hunting so I got me a box today. Will get some federal gold medal primers. He recommended RL-19 which I have some. I might also pick some H1000. I will keep the winchester brass for now. I might start .010" off the land. Hopefully I will have that ready for next week and I will be able to show some ragged holes then....

[M.O.A.]

A gun build on longrangehunt forum has a load work up that I seem to like and will use as soon as I get some more powder and bullets for my creed, anyway he picks his powder and bullet he wants to use then loads one at max then steps up till he sees the first sign of pressure then backs off two grans and that is his load. He says this has work for hundreds of guns.

[BigHorn]

Groups look "rounder" look nice and uniform. What did you change from the last ladder ???

[Nandy]

This test was using the 160 accubonds and instead of shooting 9 bullets in a row I am shooting 6.

[scope eye]

I know it's a little late in the thead but when somethings not right, after swapping barrels, I always go back and check head space first, just like electrical problems always check ground first.

Tanks Dean

[Nandy]

I'm had no doubts SSS did a good job installing the barrel. Funny thing is when i revceived the gun I could not wait to feel how smooth the timed action was so I used my go gauge to get the feel and while I was at it I used the no gauge. So inadvertently I checked the headspace and it is correct.

[scope eye]

That's good that you checked it, you can move on to other areas from there, I have tightened up factory set barrels and fixed grouping problems.

Dean

[Nandy]

Been busy and had not have a chance to update but in the latest 2 trips I found that 62.1gr of rl-19 seated at 2.723 (.010 from the lands) behind the Berger 168 vld hunting will print nicely at both 200 and 100 yds. Using Winchester brass, Federal Gold primers and only neck sizing with a lee collect die.
I tried the same load as Berger suggest using .04 increments from the land and had mixed results. Seated at 2.683 printed a better group than 2.723 but then opened up so I am trying again as soon as possible. I got lucky and the cans of powder will print the same even though it is not the same batch. I put a few loads together for deer season with the 2.723 OAL as it was the most consistent combination while I keep playing. After checking on that 2.683 I will play with H1000 next and see how it prints. The only bad thing is that the COAl is too long and I only can have one cartridge sitting in the magazine and one in the chamber. I was hopping that once I did that .04 increments steps from the land I might had got lucky but it did not happen...

100 yds


200 yds


Thanks everyone for your suggestions and help.

[Deerhunter 28]

IMR 4350


PSE EVO 57 Lbs.
Blacked out

[Nandy]

Thanks for the recommendation. For now I am only going to try the powders I have in hand. By know I have been recommended every powder that is built out there and as you can imagine, trying all that will take so much time and a lot of money. rl-19 is doing fine. will still try other rl-22 and h1000 combinations.

Thanks!

[CWPINST]

Try 140gr. Sierra Pro-Hunters and the Rl-19. If a gun won't shoot a Ballistic Tip or an Accubond it will usually like the Pro-Hunter.

[jsthntn247]

Run the H-1000 from 67-71 grains with the Bergers. Mine likes 67.6, but I have a shorter barrel than you and was getting incomplete powder burn. You should find a good node around 69-70 grains.

[pbcaster45]

I've mainly stuck with heavier bullets in my 7mm Remington Magnum but the powder which worked the best for me was Alliant Reloader 25.

Bullet: Nosler 160 gr. AccuBond
Powder: Alliant Reloader 25 69.0 grs.
Primer: Federal 215
Case: Federal
LOAL: 3.323 (2.758 Base to Ogive with Stoney Point)
Average Velocity: 2995.40 fps
ES: 19.98
SD: 8.42
Comments: Bullets seated for 0.020 bullet jump to lands. Rock Creek 26 inch 1in9 twist 5R.

A 200 yard group.