338 Wm M77 Range Day

truck driver · Feb 20, 2017

Beautiful day for shooting Clear blue skies and lots of sun shine 53* F, just wish I could have done better but there is always another day.
I think the stock on the .338Wm is holding it back since I think it is flexing under recoil and needs a stiffer stock to hold it then the factory plastic stock. I think the third shot was either me or the stock but not sure which. The first shot always seems to be right at point of aim. The rifle was left to cool between shots and and first shot was from a cold barrel and third shot was from a warm but not hot barrel. The heavy barrel on the .338 doesn't heat up like my 7mmRem or my 35/AI which are a lot thinner.
I had the 210gr PT running just over 2900fps.

hereinaz · Feb 20, 2017

Don't discount the movement of a hot/warm barrel, especially if it is the third shot, always. I was shooting these three groups as part of an OCW test, one shot in each group then repeat, from left to right. I shot two at each bullseye, then the range went cold. The first two shots for each group is in the bottom right of the group.

I let my gun cool for almost 45 minutes, then made the last three shots. You can see my point if impact for my first two shots on the third round was higher and left from a cold barrel vs. a warm barrel. By the time of my third shot, it was back closer to the group that was shot on a similarly warm barrel, but still not a hot barrel. And, by the way, the far right was almost to max pressure...

I was surprised at this, and will never zero a hunting rifle on a warm barrel ever again. A target or varmint rifle is different, but I will still map the cold bore shot for them.

I was shooting a 7 rem mag from a 26" heavy sporter contour...

Blackbear3 · Feb 20, 2017

Looks like you will have to do some work to get it to shoot consistent groups, but it's close already. Nice to have something to play with this time of year.

jimbires · Feb 20, 2017

Rodger , the first shot is the important one for a hunting rifle , and man it's putting it right there . what is your bullet jump ? can you reach the lands and still feed from the magazine ? how I go about seating depth is I start at a certain distance from the lands , or I start out at magazine length if I can't reach the lands and feed from the magazine . working with a Partition I'd start out with a 0.020 jump , IF it will feed from the magazine . if it is to long for the magazine I'd start with magazine length less about .010 or .015 so it will reliably feed .

I'm starting to see finding seating depth first is a plus , then work powder charge . " I think " I'm finding that a good seating depth holds the same through the powder charge range . my last couple load work ups I've played with seating first at the mininum powder charge . when I find my best seating then I've worked the powder charge .

truck driver · Feb 20, 2017

hereinaz":wsk7bxcp said:
Don't discount the movement of a hot/warm barrel, especially if it is the third shot, always. I was shooting these three groups as part of an OCW test, one shot in each group then repeat, from left to right. I shot two at each bullseye, then the range went cold. The first two shots for each group is in the bottom right of the group.

I let my gun cool for almost 45 minutes, then made the last three shots. You can see my point if impact for my first two shots on the third round was higher and left from a cold barrel vs. a warm barrel. By the time of my third shot, it was back closer to the group that was shot on a similarly warm barrel, but still not a hot barrel. And, by the way, the far right was almost to max pressure...

I was surprised at this, and will never zero a hunting rifle on a warm barrel ever again. A target or varmint rifle is different, but I will still map the cold bore shot for them.

I was shooting a 7 rem mag from a 26" heavy sporter contour...

Thanks for the info I'll give that a try when I reshoot these two loads.

jimbires":wsk7bxcp said:
Rodger , the first shot is the important one for a hunting rifle , and man it's putting it right there . what is your bullet jump ? can you reach the lands and still feed from the magazine ? how I go about seating depth is I start at a certain distance from the lands , or I start out at magazine length if I can't reach the lands and feed from the magazine . working with a Partition I'd start out with a 0.020 jump , IF it will feed from the magazine . if it is to long for the magazine I'd start with magazine length less about .010 or .015 so it will reliably feed .

I'm starting to see finding seating depth first is a plus , then work powder charge . " I think " I'm finding that a good seating depth holds the same through the powder charge range . my last couple load work ups I've played with seating first at the mininum powder charge . when I find my best seating then I've worked the powder charge .

I started at Nosler recommended OAL 3.340" which gives .338" of bullet in the case neck. I do know how far it is to the lands and will revisit that on the next loading. These were primarily chronograph velocity loads to tune QL. I ran three different bullets and weights which I didn't show because they were just try me loads and not important. In all I put 23 rounds down the barrel today in the .338 WM and another 12down the 7mm Rem which is fairly well about done except for tweaking.

hereinaz · Feb 20, 2017

jimbires":34wosyqi said:
Rodger , the first shot is the important one for a hunting rifle , and man it's putting it right there . what is your bullet jump ? can you reach the lands and still feed from the magazine ? how I go about seating depth is I start at a certain distance from the lands , or I start out at magazine length if I can't reach the lands and feed from the magazine . working with a Partition I'd start out with a 0.020 jump , IF it will feed from the magazine . if it is to long for the magazine I'd start with magazine length less about .010 or .015 so it will reliably feed .

I'm starting to see finding seating depth first is a plus , then work powder charge . " I think " I'm finding that a good seating depth holds the same through the powder charge range . my last couple load work ups I've played with seating first at the mininum powder charge . when I find my best seating then I've worked the powder charge .

jimbires is right, your first shot is the one that counts for hunting, and your #1 and #2 shots combined as a group are better than even one group with the third shot. Given those, I would say that having the third shot jp every time is less likely you or the plastic stock. If it throws the third shot on a warm barrel consistently, that might be the problem...

I bet if you map your shots, that your third and subsequent shots will move, because it doesn't look like you are the problem... And, if you shoot a fourth or fifth, the group will be opened up, though they could be closer just due to the statistical variance.

Also, though the barrel may not be hot enough to make all the difference, could it be your powder gets hotter in a "warm" chamber and increases pressure? How long from the time you chambered till you shoot can make a small difference too. From a nice 50 degree day to a 100 degree barrel is a difference affecting pressures.

truck driver · Feb 20, 2017

The powder is RL17 which I haven't loaded much of so I don't know if it's temp sensitive or not.

jimbires · Feb 21, 2017

truck driver":3d7wa1nf said:
hereinaz":3d7wa1nf said:

Don't discount the movement of a hot/warm barrel, especially if it is the third shot, always. I was shooting these three groups as part of an OCW test, one shot in each group then repeat, from left to right. I shot two at each bullseye, then the range went cold. The first two shots for each group is in the bottom right of the group.

I let my gun cool for almost 45 minutes, then made the last three shots. You can see my point if impact for my first two shots on the third round was higher and left from a cold barrel vs. a warm barrel. By the time of my third shot, it was back closer to the group that was shot on a similarly warm barrel, but still not a hot barrel. And, by the way, the far right was almost to max pressure...

I was surprised at this, and will never zero a hunting rifle on a warm barrel ever again. A target or varmint rifle is different, but I will still map the cold bore shot for them.

I was shooting a 7 rem mag from a 26" heavy sporter contour...

Click to expand...

Thanks for the info I'll give that a try when I reshoot these two loads.

jimbires":3d7wa1nf said:

Rodger , the first shot is the important one for a hunting rifle , and man it's putting it right there . what is your bullet jump ? can you reach the lands and still feed from the magazine ? how I go about seating depth is I start at a certain distance from the lands , or I start out at magazine length if I can't reach the lands and feed from the magazine . working with a Partition I'd start out with a 0.020 jump , IF it will feed from the magazine . if it is to long for the magazine I'd start with magazine length less about .010 or .015 so it will reliably feed .

I'm starting to see finding seating depth first is a plus , then work powder charge . " I think " I'm finding that a good seating depth holds the same through the powder charge range . my last couple load work ups I've played with seating first at the mininum powder charge . when I find my best seating then I've worked the powder charge .

Click to expand...

I started at Nosler recommended OAL 3.340" which gives .338" of bullet in the case neck. I do know how far it is to the lands and will revisit that on the next loading. These were primarily chronograph velocity loads to tune QL. I ran three different bullets and weights which I didn't show because they were just try me loads and not important. In all I put 23 rounds down the barrel today in the .338 WM and another 12down the 7mm Rem which is fairly well about done except for tweaking.

ok , I don't think I'd want much less bullet in the neck for hunting ammo . looking at a picture of the brass , you have the bullet base about right at the neck shoulder junction . I think I'd still check my jump to the lands .

SJB358 · Feb 21, 2017

My opinion, seat them shorter and walk that 3rd round in. Seems consistent enough to me that it probably wants to be seated a little shorter. 2900 with a 210 is a freight train.

elkhunternm · Feb 21, 2017

Try IMR-4350 and see what kind of groups you're getting. Also,I don't worry about the OAL,I seat the bullet till it fits in the magazine and feeds into the chamber with no problems.

Don't pigeon hole yourself to just one powder,try several,or if you want try different primers. I like the CCI 250 mag primer.

Rol_P · Feb 21, 2017

Rodger, the IMR 4451 works well in my '06 with 180 gr Partition so you might try it. It is supposed to be temp stable. Good luck Rol

longrangehunter · Feb 21, 2017

TD try a different powder. I think IMR-4350 would also be a good choice, I've used it in the 8mm Mag. and the accuracy was printing 1/2" groups! Considering the gun I was loading it for...... a old beat up Rem. 700, even I was surprised at what I had worked up.

jimbires · Feb 21, 2017

SJB358":1pog6hci said:
My opinion, seat them shorter and walk that 3rd round in. Seems consistent enough to me that it probably wants to be seated a little shorter. 2900 with a 210 is a freight train.

it would sure be worth a try . he has lots of time to play around and see if it will tighten up .

Silent Sam · Feb 21, 2017

If could only have one bullet for my 338 it would be the 210 Partition. It just works. I also use I4350. How is your barrel re copper fouling?

OU812 · Feb 21, 2017

210's are an excellent choice but IMO RL-19 or 4350 would be a better choice for the 210 over RL17.

truck driver · Feb 21, 2017

Silent Sam":2qpzhi2u said:
If could only have one bullet for my 338 it would be the 210 Partition. It just works. I also use I4350. How is your barrel re copper fouling?

For stainless steel barrel not bad at all. I expect it to get better as it smooths out, This barrel hasn't had 100 rounds down the tube yet so it is just getting broke in.

OU812":2qpzhi2u said:
210's are an excellent choice but IMO RL-19 or 4350 would be a better choice for the 210 over RL17.

Right now RL17 is what I have on hand and once I get a load worked up I'll try other powders. Thanks for the info.

JD338 · Feb 21, 2017

SJB358":sgtqjcz5 said:
My opinion, seat them shorter and walk that 3rd round in. Seems consistent enough to me that it probably wants to be seated a little shorter. 2900 with a 210 is a freight train.

+1
IMR4350 and RL19 will get you where you want to be.

JD338

338 Wm M77 Range Day

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