.300WSM dropping shots

[GLC]

Has anybody had this experience?

I have a new barrel made by a very well know manufacturer, it’s a 4 groove 10tw, it was chambered by a very well know Smith, (U.S) the work is flawless and the barrel groups well at short range BUT it repeatedly drops the odd shot after 15-20 rounds, annoyingly one dropped shot last week lost me a major win, in addition the barrel does not like shooting from cool, example is 5-6 fouling shots (blow offs) then first sighter is good and the early string it hammers, however when you transition to next distance and the barrel is cool it takes 2 sighters to return to normal elevation, then it will shoot well for 5/6 shots and then I get dropped shots and elevation, however mostly dropped shots at 6 oclock.

I have verified front rest and rear bag, rifle tracks smooth and has a Rad, I have shot 17 shots over chrono with nothing unusual, ES around 15. Nothing that would drop almost 1 moa.
Load development was extensive and thorough, 3 powders tested and it showed promise with 2 I chose R16 as 4350 is now not available in U.K. and I figured no point in using it.
Bullet is Berger 215 hybrid, speed 2870-2880.
Extensive tuner testing also performed and the best tune selected.
Brass is idod turned and cases are prepped to good standard, ES and SD were good, loads were repeated to verify.

My theory is the barrel doesn’t react well to the powder fouling and increase in temp, then when it cools the process is repeated once barrel heats, now this is pair fire not string.

Any suggestions/theories before I pull the barrel?.
I do also have another barrel which exhibits this issue, same manufacturer twist etc.

One thought I had was to try a single based slower powder like 4831sc ?

Thanks In advance.

 

[Jet]

I would try shooting it dirty before pulling the barrel

 

[Steve Blair]

Gary - I've been through a few .300 WSM barrels from Brux and Krieger, 9.75" and 10" twist, respectively. All were shot with H4831SC and shot very reliably. SC and Russian primers (both LR and LRM) provided very low ES, usually below ten fps. All barrels were 34" and, as you know, always 230 Hybrids.

 

[GLC]

I would try shooting it dirty before pulling the barrel

Good suggestion, however that will mess with my OCD…
Seriously though it’s still popping one or two out after 30 shots, so I am wondering how dirty would it need to be and how long it would last ?
Only way to find out is to test it, however longer ranges not so easy to get currently, I’m wondering if you would see it at short range, I suppose you would?

 

[GLC]

Gary - I've been through a few .300 WSM barrels from Brux and Krieger, 9.75" and 10" twist, respectively. All were shot with H4831SC and shot very reliably. SC and Russian primers (both LR and LRM) provided very low ES, usually below ten fps. All barrels were 34" and, as you know, always 230 Hybrids.

Hi Steve
Thanks.
Maybe I’m unlucky, however SC was my next to test and I will do so before binning, Barrel was neither of those but it does begin with a B…

 

[ebb]

I may be missing the point, so don't be cruel. If the barrel is reacting to excessive fouling could a powder that produces less be the ticket? I have a 6.5-284 that I liked H4831 in till I used N165.. After that I never looked back. I am sold of the VV powders. The 165 that I use is cleaner and cooler burning than any of the others Ive tried and shoots just a little better.

 

[No i deer]

Hi Gar.
I too would say try N165 before you pull the barrel.
As you know I'm not a 300wsm shooter but my saum did shoot great on N165 and I hope my new barrel does.
If it continues to throw flyers something isn't quite right.
Could it be a dodgy batch of primers..?

 

[GLC]

Thanks Gents
Never had any decent results with 165 in a .300wsm. However no harm in trying.
Will also reduce original load as it’s quite peaky on QL.

 

[RDavies]

Another vote for H4831sc and Russian primers. My 300WSM heavy gun loves this combination with 215s. Velocity spreads were great, it seems quite temperature stable and fouling never seemed to be an issue.

Gary - I've been through a few .300 WSM barrels from Brux and Krieger, 9.75" and 10" twist, respectively. All were shot with H4831SC and shot very reliably. SC and Russian primers (both LR and LRM) provided very low ES, usually below ten fps. All barrels were 34" and, as you know, always 230 Hybrids.

 

[No i deer]

If you have a stash of H4831sc that is..
Unfortunately it's no longer available in the UK along with many other of the hodgdon extreme powders which was the favourite for most.

 

[Willow]

I had one for a couple of years and only stopped using it due to energy limit restrictions at most ranges in Australia make it a bit pointless. However, RL23 and S&B primers behind Berger 215gr hybrids produced great accuracy and I did not suffer flyers from vertical. 2213sc (H4831sc) is the other obvious choice powder to run. I did try ADI2209 (H4350) and it didn't like it.

 

[coldboreshot]

Has anybody had this experience?

I have a new barrel made by a very well know manufacturer, it’s a 4 groove 10tw, it was chambered by a very well know Smith, (U.S) the work is flawless and the barrel groups well at short range BUT it repeatedly drops the odd shot after 15-20 rounds, annoyingly one dropped shot last week lost me a major win, in addition the barrel does not like shooting from cool, example is 5-6 fouling shots (blow offs) then first sighter is good and the early string it hammers, however when you transition to next distance and the barrel is cool it takes 2 sighters to return to normal elevation, then it will shoot well for 5/6 shots and then I get dropped shots and elevation, however mostly dropped shots at 6 oclock.

I have verified front rest and rear bag, rifle tracks smooth and has a Rad, I have shot 17 shots over chrono with nothing unusual, ES around 15. Nothing that would drop almost 1 moa.
Load development was extensive and thorough, 3 powders tested and it showed promise with 2 I chose R16 as 4350 is now not available in U.K. and I figured no point in using it.
Bullet is Berger 215 hybrid, speed 2870-2880.
Extensive tuner testing also performed and the best tune selected.
Brass is idod turned and cases are prepped to good standard, ES and SD were good, loads were repeated to verify.

My theory is the barrel doesn’t react well to the powder fouling and increase in temp, then when it cools the process is repeated once barrel heats, now this is pair fire not string.

Any suggestions/theories before I pull the barrel?.
I do also have another barrel which exhibits this issue, same manufacturer twist etc.

One thought I had was to try a single based slower powder like 4831sc ?

Thanks In advance.

Run this by the barrel mfg for their input.

 

[GLC]

Run this by the barrel mfg for their input.

Have done just that and we are engaging.
Thank you.

 

[paulT]

How many Rounds through barrel also have you scoped barrel for wear in throat along with possible carbon ring.

 

[GLC]

How many Rounds through barrel also have you scoped barrel for wear in throat along with possible carbon ring.

200-250 round (barrel is almost new) develops a carbon ring very quickly which takes some effort to remove also fouls more than I am happy with.


Edit/update
I’ve decided to remove the barrel for now. I need a competitive rifle soon so rather than waste time I will re visit if I have the time and inclination.

 

[X Count]

Shoot a match or two with the lab radar set up and see if there is any correlation of fps and low shots.

I had something similar years ago ( before mag speed or lab radars were available) and it turned out to be a dud batch of primers having minute hang fires.

Measure bullets and check pressure ring diameter variations.

Also other barrels that have needed to foul or warm up before they would shoot seemed to be on the bottom of the node. Increasing powder charge .3gr ish helped

 

[GLC]

thanks for your info it is appreciated and noted.
however i did run this barrel with my chrono previously Es was ok (not fantastic but defo not enough to drop me 1 moa) however this was not for 20 shots.... I use the same primers in two other rifles which have been ok.
this load is quite warm already so my inital thoughts were to back it off, however Barrel has now come off until I have more time to mess with it, gotta have a competitive Barrel for the Euro Champs in Sept.

 

[Zero333]

I had one for a couple of years and only stopped using it due to energy limit restrictions at most ranges in Australia make it a bit pointless. However, RL23 and S&B primers behind Berger 215gr hybrids produced great accuracy and I did not suffer flyers from vertical. 2213sc (H4831sc) is the other obvious choice powder to run. I did try ADI2209 (H4350) and it didn't like it.

I was also gonna suggest Sellier & Bellot primers because they're the closest to Russian ones. All the thousands of S & B primers I used were on the smaller side and slide in the pockets easier. Regardless of cartridge, I always use them in virgin brass since primer pockets can be fairly tight. Especially with Lapua Brass.

 

[SteveW]

I have a new barrel made by a very well know manufacturer, it’s a 4 groove 10tw, it was chambered by a very well know Smith, (U.S) the work is flawless and the barrel groups well at short range BUT it repeatedly drops the odd shot after 15-20 rounds, annoyingly one dropped shot last week lost me a major win, in addition the barrel does not like shooting from cool, example is 5-6 fouling shots (blow offs) then first sighter is good and the early string it hammers, however when you transition to next distance and the barrel is cool it takes 2 sighters to return to normal elevation, then it will shoot well for 5/6 shots and then I get dropped shots and elevation, however mostly dropped shots at 6 oclock.

In my experience, the symptoms you describe sound very much like it could be an ignition issue. I'm uncertain if this is a new action you have employed, but regardless, you might try a new striker spring before giving up on the barrel.

 

[RDavies]

In my experience, the symptoms you describe sound very much like it could be an ignition issue. I'm uncertain if this is a new action you have employed, but regardless, you might try a new striker spring before giving up on the barrel.

His crony readings were not too bad from what he says. Some barrels are hummers and some are just bummers. (or just not great). It is sounding like a barrel change i the next tuning step if he has a big comp coming.

thanks for your info it is appreciated and noted.
however i did run this barrel with my chrono previously Es was ok (not fantastic but defo not enough to drop me 1 moa) however this was not for 20 shots.... I use the same primers in two other rifles which have been ok.
this load is quite warm already so my inital thoughts were to back it off, however Barrel has now come off until I have more time to mess with it, gotta have a competitive Barrel for the Euro Champs in Sept.

Just wondering, what was your ES/SD?

But, yes, sounding like it is time to switch out the barrel.