My 300 Win Mag Sendero

[Bishop]

Took my Sendero SF II chambered in 300 win mag out for this sunday to seriously take a look at how I could group with it at 100yd. I put a leupold vx-3 6.5-20 LRT with the varmint hunters reticule on top of it and leupold mounts *what the smith recommended*. I also had him put a jewell trigger in it as well. Other than the trigger the rifle is completely stock.

Got this rifle last year got her set 4 3/4 inches high at 100 yds *was able to shoot a few times at 300 the weekend before season opened and it was reasonably close to where I wanted it at that range, just a bit high and blam! hunting season was here before I had a chance to actually see how well she would Group. Took three whitetails off my stand all three within 10 yards of the same spot that I had lasered at 351 yds. I also took 2 coyotes within minutes of each other on the side of the hill just to the east of my stand across the draw. We had lasered the hillside's farthest point I could shoot *because of vegetation* at 420 yds.

I had never been in an area that had much of a coyote population in it that would move in the daylight so didnt have much experience with hunting coyotes, durn if they arent like smoke on the water, appearing out of nowhere in and instant and never stopping.

First coyote appeared halfway up the hill out of NOWHERE just looked like it materialized out of the grass about what looked to me about 20 yards shy of the woodline we had previously lasered. The sucker never stopped moving as I scrambled to get my gun moved over *Shooting off of a fallen down tree trunk*. It was running straight down the hill at about 400 yards and I had about a 45 degree (downward) shot, just guessing, figured my bullet wouldnt drop as much as it would normally on a level shot so I put the crosshairs right between his shoulder blades and squeezed one off. No coyote in sight and I think "Dadgumit! I missed".

Aggravated at myself for missing I dejectedly chamber another round and notice movement out of the corner of my eye! There he is again running up the hill! I'm excited now and get the scope on him and put it right on his head this time thinking surely I wont be shooting high at this range according to the numbers the Online ballistics calculator has been telling me (pretty much a level shot close as I could tell), I touch another one off and no coyote visible on the hillside. I'm thoroughly dejected at this point, dreading having my shirt-tails cut by my dad but after the sun goes down I drive over there and comb the hillside with a flashlight just in case I just wasnt able to see where they fell because of the thickness of the grass and to my happiness I found one laying right where I squeezed off my second shot at the coyote heading up hill *the one I thought i had missed on the first shot*.

I head down the hill just to check the spot where I had shot at the first one and HOOYAH another one down! I found a den halfway between where both of these rascals fell. No wonder they seemed to appear out of nowhere hah!

So I thought I had myself a reeeeal shooter, after all I had never attempted to shoot anything but milk jugs at even 200 yards before with any of my rifles, yes I was truly your proverbial redneck who thought that was good enough.


So I was rather surprised when I couldn't for the life me I could not shoot any better than a 1" 5 shot group at 100 yds. I shot 40 rounds total on sunday out of my rifle and accuracy didnt seem to get any worse or any better just pretty consistent 1" and never any worse than 1.5". I was taking breaks after every 5 round session and playing with my Cz,Marlin, and savage rimfires for a while in an effort to avoid unnecessary heating and throat erosion that I have read about occuring if you shoot magnums too fast and too long.

Ammo- Nosler Custom 300 win mag with 180gr Accu-bond-the 90 doller a box "hand load" ones that come in the Plastic ammo ?carton? not the normal factory ammo type cardboard box.

As soon as I got home I ordered the Speer #14 reloading manual and the Sierra reloading manual in preperation of entering the hand-loading world.

At this point I just want to try and Eliminate ammo as my accuracy flaw and narrow it down to-

A. ME and my most likely abysmal bench technique

B. The rifle

or

C. The scope

I dont have too much money to put into this at the drop of a hat so I will be working my way into it.

I would like to ask would any of you guys just go ahead and have some smithing done on the gun at this point such as- Lap lugs,trueing bolt face, blue-printing action, bedding of the aluminum bedding block on my sendero, re-crown barrel? Or would you go ahead and attempt to eliminate ammunition as a factor first?

Remember I am pretty much a nublet and will be learning from ground zero on the more technical aspects of shooting long (er) ranges. I just want to get my rifle shooting 3/4 moa at 100 or better before I dive head first into the 500-1000 yard range, because I'm assuming I am shooting no where near good enough to ethicaly engage game beyond 400 yards. Im figuring I got very lucky with those coyote's.

Any thoughts/conversation is much appreciated.


-Bishop

 

[shortgrass]

Sounds typical for 'todays' Remington, no matter which model. I'd conentrate on the ammo and getting set-up to handload. Blue printing and lug lapping are done when a rifle is re-barreled with a custom barrel not for re-installation of a factory barrel (that would have to be re-headspaced after blueprinting/lapping). I'm not one to put much time or money into a factory barrel (although, I'm still looking for all those 1/2" factory rifles that I hear about).

 

[chain]

On line groups are always better that real groups. I shoot a 300 win, it has an aftrer market trigger and nothing else. I will re-barrel when it starts to fall off. I think being diligent about your reloading and trigger time is the way to go. I have found that most of my "BAD" groups is due to operator error.

 

[Bishop]

Thanks for the advice guys. I appreciate it. Cant wait to get started hand-loading.

I was told today by a co-worker while having a conversation about shooting how he "knows a guy" that pulls off headshots on deer at 900 yards over a cornpile with his most adamantly "factory" weatherby mark V using weatherby "factory" ammunition. And that he had personally witnessed this and had to dress the 4 deer that his friend shot over the cornpile because he bet him he couldnt headshot all 4 of them.

If only I had managed to get one of THOSE rifles .

I saw in the Speer manual *went ahead and bought one at a local gun store in spite of the fact that I already have 2 other manuals on order* a section about the STW that referred to bullet "yaw" and that it had a detrimental effect on observed accuracy up until the range that the bullet "went to sleep" to use their terms and "settled in".
And that this range approached 100 yds. However there was no other reference to this in relation to other calibers that I read so far. Is this an isolated phenomenon dealing exclusively with the 7mm STW or does this characteristic assert itself on all calibers to some extent?

 

[retiredcpo]

I shoot a sendero in 7mm Rem Mag
My shooting buddy shoots one in 300 Win Mag(71 gr of H4831 sc over a 180 gr accubond)
Both are 1000+guns
The Sendero is a Great gun!
I believe handloading is a must.
I would suggest you work up a load carefullly and slowly.
As the money comes in I would
1 glass bed the action
2 Send the scope back to leupold and have the turrets replaced with m1 turrets.
3 get a good solid moa base and some good rings(I prefer seekins)
If you want some pics of what the scope would look like send me your email

 

[Bishop]

Thanks For the reply! I have actually checked out the leupold custom shop m-1 turrets and boy they sure look sharp, and Im guessing pretty handy if your cranking on the scope alot, which i plan to do in the future!

Gonna have to check out the Base/ring set you talked about though.

 

[retiredcpo]

they are nice turrets
I had mine done but i was planning on it before I ordered the scope
I wanted the VX3 because of the 94 moa of travel.
You can find cheaper rings and bases but youll be much happier down the road
if you get good ones up front(you get what you payfor)
retiredcpo

 

[royinidaho]

Hey Mr. Bishop,

Focus, Focus, Focus. Turrets and stuff are nifty only after you get her shooting well enough and come up with the drop chart.

The bullet settling in (going to sleep) has more to do with the bullet length than caliber. Generally, kind of, the longer the bullet the longer it may take to 'settle in".

If it were me, I'd shoot the 300 Win no closer than 200 yards. But I shoot every thing @ 200 yards except the rain bow shooting 338s which I zero at 300.

If shooting around 1 inch (1 MOA) @ 100 yards you're only 1/2 MOA off of center Point of Aim (POA) or 1" @ 200, 1.5" @ 300 and 2" at 400. That should explain you kill success. So what's wrong with that???

There have been suggestions posted above regarding simple accuracy improvement methods.

The first, and easiest would be to "float" the barrel. Float mean you can run a business card from forearm to recoil lug through the barrel channel.

If you take the rifle apart you'll see two raised spots, one of either side of center, at the front of the barrel channel. To free float remove these. With that load (90 bucks a box ) groups will certainly move their Point of Impact (POI) and may be larger, smaller or the same. Probably smaller though. But just probably.

Here's a nifty trick:

Get one of these things ($9.99 @ Harbor Freight) + a dial indicator. Better would be to borrow one. (Tape the bottom w/masking tape to keep from marring the barrel.
\

After removing the pressure points from the stock use this and the dial indicator to check the bedding.

• With the rifle vertical on the recoil pad mount the gizmo to the bottom of the barrel with the arm of the dial indicator resting on the forearm somewhere near the sling swivel stud. NOTE: This may take two people and be careful of the hanging lamp above the kitchen table (where this process is usually performed.)
• When set up, alternately tighten and loosen the action mounting screws. If there is much (any to some of us) movement (.003" or 0.004"shown on the dial indicator Pillar Bedding may be in order. The reading is an indication of the stress exerted on the action by improper bedding. (With the pressure points NOT removed you'll get plenty of indication of stock flexing.)

Another interesting thing to do is to loosen or remove both action mounting screws and see if the barreled action can be slid back and forth in the stock. If there is movement and you're gonna shot before bedding, hold the rifle vertical or otherwise ensure the recoil lug is hard against wood as you begin to tighten the mounting screws. (Always use a proper fitting screw driver and don't try to twist the screws off. Only 65 inch pounds of force is recommended by many. I have no idea of how much 65 inch pounds is so I make it 'plenty' tight......

Oh, and one more thing (I'm on a roll here) Ensure that the action mounting screws are NOT touching the stock. I do this by drilling the holes a couple of sizes larger.

Have fun but holey cow step a couple of steps away from the 90 bucks a box stuff. That's mighty 'spensive brass.

 

[Bishop]

If shooting around 1 inch (1 MOA) @ 100 yards you're only 1/2 MOA off of center Point of Aim (POA) or 1" @ 200, 1.5" @ 300 and 2" at 400. That should explain you kill success. So what's wrong with that???

Nothing actually wrong with it I just want better!! Part of it is my Savage .17 hmr, I can shoot as good with a 200 dollar rimfire with a 130$ Scope on it as my roughly 2000$ 300 mag. I have to get it grouping better than my squirrel gun!! I was hoping My groups would be a little better. My expectations might be a little on the high side for what I have. And in all likelyhood my "ability" may just not be on par yet.

The first, and easiest would be to "float" the barrel. Float mean you can run a business card from forearm to recoil lug through the barrel channel.

If you take the rifle apart you'll see two raised spots, one of either side of center, at the front of the barrel channel. To free float remove these. With that load (90 bucks a box ) groups will certainly move their Point of Impact (POI) and may be larger, smaller or the same. Probably smaller though. But just probably.

AHA! I floated the barrels on all my rimfires, they all had wooden stocks and I assumed they would require a bit of sanding with a dowel and some 80 grit. Upon reading your advice above I checked to see if my barrel was actually floated on My sendero it seems it is only floated to within 4 inches of the Lug *Im thinking the lug is the square block that rests within a slot cut into the bedding block within my stock correct me if im wrong* It does not appear to have the bumps at the end of the forearm within the barrel channel though. I dont know why it isnt free floating all the way back, I seem to remember checking this repeatedly right after I purchased my gun and I was able to run paper *like the cover of a notebook* all the way back to the action. Perhaps the forearm of my stock is a little flimsy?

The action does slide back and forth just a tad when I loosen the screw's also.

That contraption you showed sure looks nice, Ill look into getting my hands on one of those to perform the test you suggested.

Big Thanks for your suggestions, they pointed me to a few flaws I overlooked. This stock, in spite of the aluminum bedding block looks *to my un-trained eye* like it could definately be improved upon by a good bedding job. It is alot sloppier than I would have figured.

And I won't be buying any more expensive ammo for certain, that money is going into a shoebox for MOAR STUFF namely reloading equipment. Boy my wife will be thrilled.....

 

[roninflag]

the 300 mAG is one of the most forgiving of all rounds i have loaded for after the .222 and 308. easy to get good loads with little trial. the sendero is one of the best guns you can buy. i have loaded for 5 300 senderos, 3 7mm, 3 300 rum , 3 25-06 and a 264. they all shot less than an inch some a LOT less. for the magnums first thing we do is have a vais brake installed. you did not mention a brake. my 300 and 7mm kick less than my 6.5 that does not have a brake. we adjust the trigger or replace it with a jewel or shilen. i use lapua brass in the 300 win mags. i have killed over 250 coyotes and have seen almost that many killed. i have seen 5 killed at over 400 yards. they are a small and challenging target. yet you killed two !!you do not need a full house load for deer and coyotes. load a 165 bal tip or a 168 cbt or a 168 or 175 berger to 3000 fps. i shoot in a lot of F class matches. 500 to 1000 yards. i have yet to see a weatherby. i have shot against some very expensive guns like accuracy intl ect. i like weatherbys they are pretty, some have nine locking lugs, the cartridges were ahead of their time. the accumark and the super varminter may come close to a sendero.

 

[baldhunter]

I've had to bed the recoil lugs on my two Senderos.H.S. Precision puts a nice aluminum block to support the action,but the inlet for the recoil lug is way oversized.Once this is done,when you loosen the bolts on the stock,it won't slide and roll like it does now,the barrel action will be nice and snug in the stock.Your groups should tighten up a bunch.

 

[Bishop]

@ ronin

I do not have a brake yet, several people are trying to steer me away from it because of the noise, but I already use hearing protection, I dont know why they are so dead set against it, however I really want to get a brake installed and have been wearing out my search button reading threads about the various ones avail.

@ Baldhunter

Thanks for the tip, I will try that and see what happends to my grouping!!