Guidance needed - Sendero

Discussion in 'The Basics, Starting Out' started by Mike027, Mar 23, 2014.

  1. Mike027

    Mike027 Well-Known Member

    Mar 25, 2006
    Good morning all. I will apologize in advance for the lengthy note. Im not experienced enough to make an informed decision on my own so I am looking for some guidance to help point me in the right direction.

    I have a new Sendero SFII in 7mmRM that I am working up loads for. I had purchased this new in 2009 and I finally got around to putting a Leupold VX3 4.5x14x50 w/CDS on it this past January. I did a break-in procedure on it (instructions from Wipeout) and I have been working up loads using Sierra Gameking 160 grain spitzer boat tails and Berger 168 VLDs. I have attached a pdf that shows the typical groups I have been getting.

    This is the first rifle I have owned that has really given me groups that are consistently around that half inch to three quarter inch range at a 100yds and I dont want to mess it up (thats why Im posting here with my questions).

    At the last range session I fired about 25 rounds. At the end of this session my cheek bone was starting to hurt. I also noticed that the recoil causes the rifle to bounce off the bag so much that in the follow thru the target was no longer in my view (barrel typically finishes pointing left and above the target in a 10 or 11 o'clock position).

    I have been researching muzzle brakes and I thought perhaps adding a brake (I was looking at Gentry) would be of benefit to manage the recoil because I really enjoy practice shooting. I had also considered having the stock/action glass bedded at the same time (both items to be done by local smith). My thinking was that the glass bedding could possibly help tighten up groups with the Bergers.

    I showed my target groups to a friend of mine and he said that adding a brake or doing bedding could possibly ruin the accuracy by changing the harmonics of the barrel and he recommends that I leave as is (as you know this is easier said than done....this stuff is addicting).

    I dont want to do anything that would negatively impact the accuracy potential here. This rifle will be used for elk/deer in Idaho and I would like to work myself up to the point where I can be proficient out to 500 yards.

    So Im hoping that folks experienced with muzzlebrakes can chime in and let me know if adding a brake could destroy the accuracy I have. Also based on the groups that Im getting do you think it would be worth it to take it in for glass bedding.

    On a side note this rifle really seems to like the Gamekings and RL 19 which is great and I dont think the temperature sensitivity issues would impact much between my home state of Michigan and Idaho but I would really like to shrink down the Berger groups. I will be doing more testing this week with Bergers and H1000 and firing at 200 yards. I will be increasing the powder grains to get more velocity. Both the Bergers and Gamekings seem to like seating at .010 or closer.

    Any recommendations on the muzzle brake and bedding idea (or anything else) is appreciated.

    Thanks. Mike

    Attached Files:

  2. roninflag

    roninflag Well-Known Member

    Feb 27, 2006
    I have no experience with putting a brake on after startling shooting. mine shoot great with a vais brakes installed. mine do real well with re-19 also.

  3. rcol317

    rcol317 Well-Known Member

    Feb 23, 2012
    Congrats on a good rifle. I asked a similar question a few weeks ago on a 300 Ultra Sendero I have. I was directed to Snowy Mountain Rifles,‎ to install their brake. I have the Vias brake on a couple small calibers but the Snowy Mountain brake is better suited for large bore has the ports out the side and top not all around like the Vias brake. Blows less dirt in your face when shooting on the ground. I'm shipping my Sendero to them. Good luck
  4. Lefty7mmstw

    Lefty7mmstw Well-Known Member

    May 13, 2012
    We have shot the savage striker pistols with the adjustable brake ( if you call on or off adjustable :rolleyes:) on them and it really didn't make a difference in accuracy for a given load. It was a bit easier to shoot well though with the brake on I suppose. I'd look at a good recoil pad first and if that isn't enough send her in for a brake.
    I'm not much for brakes, and only have one of the 11 rifles I own braked.... mostly because it came that way. That said, if you think you need less felt recoil, you probably do.
    As to powder temp. sensitivity, that is much to do about nothing if you've shot the rifle and know your drops in the conditions you will hunt in. I shoot more rl than any other brand and I live in North Dakota. I wish there were a magic potion that made everything the same no matter the temp., but even if you can get your speeds the same at all temps., your air density, barrel harmonics, teeth chattering, and a number of other things will be different.
  5. gilmillan1

    gilmillan1 Well-Known Member

    Dec 8, 2012
    I would definitely bed the stock of the rifle and free float the barrel. These upgrades will only help the accuracy of the rifle. After doing that, I would shoot the rifle again to test accuracy. I think that your rifle is jumping because you are not loading your bipod. Do you know how to load a bipod? I have the same rifle and I did the upgrades I mentioned and added a jewel trigger. This is one of my favorite rifles. Try loading your bipod.
  6. Mike027

    Mike027 Well-Known Member

    Mar 25, 2006
    I don't have a bipod (yet). I've been shooting off a Caldwell bag. Probably not the best rest but all I have at the moment.

    One thing that came to mind today was that because Im using Talley medium height scope rings to accomodate the 50mm objective I'm probably not getting a good cheek weld. Maybe a strap on cheek rest would help with the recoil issues. I see there are some good ones out there. Mike
  7. Doublezranch

    Doublezranch Well-Known Member

    Mar 24, 2011
    If your rifle is a sendero, you should have a aluminum bedding block in the h&s stock. Make sure that the barrel is indeed free floating. Then purchase a good muzzle brake. Have a smith you trust install your brake for you. Installing muzzle brakes in the past have increased my accuracy not diminished it. It may change your zero, or tighten a group up but should not diminish accuracy. Here is my 7 RUM sendero with a Assassin brake installed.

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  8. lamiglas

    lamiglas Well-Known Member

    Mar 20, 2008
    First let me say that I really believe you will not regret putting on a brake. I have worked up loads for several rifles over the last couple of years where the owners either had to save up for a brake, or wanted to make sure the gun would shoot good before spending money on a brake and or bedding. Every time (except one gun) we had to change the load slightly after the work was done. I have heard from my smith and others that a brake doesn't necessarily make your gun shoot better, but allows you to shoot it better. I can say 100% that every gun has ended up shooting better For us with the brake than it did before. Again, I would bet though ( based on my experience with several rifles) that there is a good chance you will have to change your load slightly. Well worth it though in my opinion. We have found that the sweet spot only changes by .5 grain one way or the other and has always shot even better than before. Type of brake etc could make a difference? Maybe with your set up there will be no difference? Lastly, knowing what I know now, I strongly encourage all my friends to wait until brake and bedding is done before load work up. saves time and money in the long run. I would go for it, but its your call. Good luck with your decision.
  9. blacknzr1

    blacknzr1 Well-Known Member

    Jan 28, 2012
    I have a sendero in 7mm mag also. I used to worry that I couldn't shoot it well.
    I bedded it and later on replaced the trigger. I do also have a butt pack type thing on the butt, it has a piece of padding stuck to the underside of it for correct check weld.
    I did think I might need a suppressor or muzzle brake.

    I then started reloading with the 162 amax and h1000, which showed me something... I can shoot it well! off the concrete with a harris bipod with spikes and a rear bag in prone I can shoot a .3 inch group at 100 yards. it was the factory rounds that were making random groups.

    im glad I didn't put a muzzle brake on it, I hate those noisy things.
    im sure you too can shoot yours well. it does take a bit of driving though.

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  10. Mike027

    Mike027 Well-Known Member

    Mar 25, 2006
    Thanks for the replies guys. I have some thinking to do. I currently have another rifle in at the local gunsmith for glass bedding. When I pick up that rifle I may ask them some questions about the muzzle brake and at least have them bed it for me and tune the trigger. The shop is Dick Williams Gun Shop in Saginaw. They have done some trigger work for me in the past and I have heard lots of good things about them. According to their website it appears they specialize on installing the Gentry Quiet Brake.
    I do like the idea of being able to stay on target better after the shot. Thanks again all. Mike
  11. WildRose

    WildRose Well-Known Member

    Feb 3, 2011
    The only way you will hurt your rifles accuracy with the upgrades proposed is if they are not done properly.

    The Gentry Quiet Brake is very effective but it is a 360 deg discharge brake which means a whole lot of crap blowing back in your face if you ever need to shoot it prone in the field or resting off of a tree etc.

    Install the Snowy Mountain Rifles Break and you will never regret it.

    Once you've adjusted the trigger, floated, bedded and added the brake you are going to really be able to enjoy shooting your rifle.

    As for the cheek weld, take a look at the accu-riser cheek rest, they work very well. If you want a little more utility of it then get one of the padded cheek rest/stock packs instead.
  12. idefendem

    idefendem Member

    Jul 30, 2012
    congratulations on the Sendero, you will not be disappointed. I have the same gun, same caliber and had about the same groupings after break in. here are a few suggestions: pull the stock off and look at the bedding block. you will notice a few "rubs" where the receiver is touching the bedding block. I have the same gun and found (to my horror) 3 places with HUGE scuffs. be sure to look at the recoil lug; you will probably notice a rub on one corner of that as well. whomsoever had the idea of the bedding block was a genius. BUT, whoever thought that a round Rem M700 receiver would fit into a "V" block was an idiot. they don't match up. the HS Precision aluminum block is great for stiffness but it needs to be pillar-bedded.

    To Bed or Not to Bed; the answer is: yes, of course

    step one: go to and buy a set of bedhead pillars (washers really (about $20.00 bucks for a set)). fiddle around with stacking them to various heights until you can slide a dollar bill at all points between the receiver and the bedding block. I installed them at about .025 height on my block to finally get complete clearance on my receiver. then bed the pillars and the action into the aluminum block. I used Steel Bed bedding. it is a tad spendy (about $55.00), but it contains a high percentage of atomized stainless steel, thus it is the strongest and hardest bedding I could find. you can do this yourself. there are a zillion videos on YouTube demonstrating the procedure if you need a visual. just use care, take your time (it really is fun to do) and put masking tape and release agent on every imaginable surface. I mean every where! it will be messy if this is your first time doing it.

    Muzzle break: no, ... not yet. The 7RM still has too much recoil to stay on target after a shot, even with a muzzle break. it does reduce recoil and you will recover your sight picture quicker with one, but there is a better way for now. especially if this is a gun you are going to hunt with-and you WILL want to hunt with this gun.

    step 2: buy a pas (sp?) shoulder pad in the "magnum" variety. they are about $25 to $30 and wear it under your shirt or jacket for those days at the range. it takes care of recoil on my .458 win mag and my "mule," a Ruger 1A in 45-70 shooting hot loads, off the bench! you can always get a muzzle break later. the Sendero is heavy enough to absorb a lot of recoil and the shooting pad takes care of the rest. the guy on the bench next to you at the range (and the guys a few benches down from him) will thank you. moreover, you wont have to wear double ear protection while hunting, be blinded by dust and crap blown out by the blast when shooting prone or deafen the woodland fauna with every shot.

    you can always have a muzzle break installed later if you really, really want or need one. but for about $100.00 you can increase the accuracy and decrease the recoil without making a trip to the gunsmith.

    my pet load is the 168gr. (hunter-hybrid PN#28501) VLD's set .002 off lands (it also shoots "lights out" set .030 off lands-go figure), a healthy dose of H1000 (it is slightly over Berger Manual published max, so I will not list it) lit by a F215 primer and neck sized, once fired Win brass. it is my freezer fillin', 1000yd steel-ringing, fun as hell rifle. enjoy yours.

    good luck

  13. Mike027

    Mike027 Well-Known Member

    Mar 25, 2006
    Roger I went to the range on Sunday and really tried to pay attention on the level of recoil and how I was holding the rifle. At the end of the session I really wondered if the brake would help keep me on target for follow-up shots. I think the addition of the cheek rest will help. I will look into the shoulder past as well.

    I tested some loads at 200 yards. I couldn't stay long but here is what I came up with:

    .697" = Sierra 160 g Sierra Gameking with 62 grains of R19
    .2681"= Berger 168g with 68.5 grains of H1000
    1.627" = Berger 168g with 68.6 grains of H1000
    1.802" = Berger 168g with 68.7 grains of H1000
    1.802" = Berger 168g with 68.8 grains of H1000
    The above loads were with Federal 215 primers.

    I tried one load with with the Berger using 67 grains of H1000 but with a CCI 250 primer and that group measured 1". I was quite pleased to see the results with the CCI as the Fed 215s are getting scarce around here.

    Thanks for the tip on the pillars. To be honest I have not pulled the stock to check the bedding but I will do that. I don't want to mess up a good meat getter so I may ask the local smith to look it over and do the necessary work.

    Thanks all for the suggestions. Mike