Sendero Accuracy Trouble

Hey i just purchased a rem sendero 7mm , just came back from the range, my grouping was all over the place , ammo was rem 140gr. Core lock , what ammo would you guys recommend ????
 
Hello LR700...

Please define, in inches... "all over the place" for us. It may be a mechanical problem, it may be a shooter problem... know what I mean?

C
 
Every rifle is different and what works great in one Sendero might give shotgun pattern groups in another Sendero. The only way to know what shoots best in your rifle is to try different ammo.
 
Need more detail....

How you are shooting- Sandbagged solid rest?

Is it just you that can't get the gun to group? Anybody else take a crack at it?

Are all the screws (action, scope rings/mounts) tight?

The only times I ever had rifles "shooting all over the place" were when there was mechanical sighting issue- one had a loose scope mount and the other had a rear sight that was loose enough in the dovetail that you could push it sideways with light finger pressure- both moved every time the rifles were fired.
 
Pictures of the targets would be helpful. Certain patterns can help pinpoint the problem(s).

Rifles may shoot different brands, or lots within brands better than others. A recent gun magazine found a batch of 180 grain Core-Locts to shoot 2-3" worse than other brands. We've normally found that brand/bullet weight to shoot under 2" at 100 yards.

Try Winchester 150s, Federal Premium 165, Hornady 150 to 180grain. Some rifles shoot best with 168 grain target loads, but they're not good for hunting.

If the rifle still doesn't shoot well, and you are normally a very good shooter off the bench, try a different scope and mounts.

If you're a novice at bench shooting, examine your shooting technique, including having someone load snap-caps within a magazine, to check if you're flinching.
 
I will introduce a controversial point of view.Knowledgable folks with opinions I respect disagree,make your own choice,

A 7mm mag has a tight twist,about 1 in 9.It typically shoots heavy for caliber bullets(I like 160-168).We put a big charge of slow powder behind that heavy bullet riding in tight twist,there is a lot of friction and the slow powder makes for heat dwell time.It is significant enough you do not get real long barrel life with one,wild guess,if you get 4000 rounds,that would be real good,(I said,wild guess!)

You are pushing or exceeding 3000 fps

All those factors working together can make for a barrel all cheezed up with copper fouling,and it won't shoot.

I do not think more moderate cartridges like the .308 or 30-06 typically show as much problem,and not removing fouling may work for them.Like I said,folks that know more than I do just wrote they don't remove copper.

If you do,maybe bore-tec-eliminator,a Montana black nylon bristle brush,a clean,straight one piece rod and a bore guide,try cleaning the copper out of it.I have a couple of decent shooting tight twisted over 3000 fps rifles,and they start to open up after about 50 rds from cleaning.

Just for fun,you might risk buying a box of 50 Accubonds ,150 gr .Try those.From memory,verify with the manual,IMR 4350,H-4831,H-1000,Re19 and 22,someplace in there is a powder that will work.

There are a lot of other fine bullets!!I only mentioned the Accubond because it is tough enough to hold together with a 7mm mag,and typically is very accurate

Add to that,its a Rem production barrel.Is what it is,not bad,but not a hand lapped high grade barrel.Not a big deal,but in my opinion,less smooth and more likely to foul.
 
I that's the weight of bullet you prefer, try the 139 grn BTSP's from Hornady Custom ammo.:) as far as a factory load goes they're pretty consistant! But if it's a handload your looking for, then ask for it.
 
Do a couple things (after checking all your scope mounting screws)...

Fire a factory round and take the fired case and rotate it 90º and try to put it back in. That would show if you had a oval (out-of-round) chamber.

Then if that's okay, take it to a gunsmith and have him check the headspace. Shouldn't take long as he should have the headspace gauges.

Check the torque on the action receiver screws to the factory spec.

If the scope mounting screws are tight and the chamber is good and the stock receiver bolts are the correct torque, it should shoot.

140 gr bullets should shoot fine in that rifle. That's the normal weight.

And I hope you have a solid rest (bench using sandbags or similar) and are squeezing the trigger!
 
Long Range 700:

It sounds like your rifle is shooting dinner plate sized groups. If so, I would check out the integrity of not only the scope; but also, the integrity of the mounts. If you have a Tasco or a Simmons I would replace it with a Leupold or Burris. If you have a good scope and your groups are more like three inches I would switch brands of ammo and bullets weights. I hardly think that your rifle is at fault.

Semper Fi.

Gunnery Sergeant
Clifford L. Hughes
USMC Retired
 
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