Help required...

DS Mad

Well-Known Member
I just acquired a box of Barnes TSX 85gr in .243 i have been loading my lead bullets with Vhitavouri N150 that i still have 3kgs of. so i have loaded just two lots of 4 bullets to try out. 37.4 gr and 38.4 gr. Vhitavouri web site tells me top powder weight is 39.4 for this bullet weight. On firing the 37.4 gr the first shot marked the head and the secound shot had blown the priming cap out. so i stopped. firstly why is this happening when i am two grains below the max and secondly i have been told that i need to be near the max powder weight to get the speed so they mushroom. apart from changing powder does any one know and not guess where i am going wrong. do i keep reducing powder weight ? .. I shoot a Tikka T3x around i year old.
 
C.O.A.L is 2.0310" the books tells me 2.0450" so its about there. The barrel was given a really good clean before shooting. The 80 gr and 100 gr lead Sierra bullets find its just the copper 85 gr i am struggling with.
 
@DS Mad you're starting near the maximum loads. You're also seating the bullets really deep

I would start at 33.2gr and work up in 1gr increments to find pressure. See the Vihtavuori & Barnes recommended seating depths - both very similar (pick one).

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Sorry total length is 2.6260 ... No i don't crimp the bullets
 

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Sorry total length is 2.6260 ... No i don't crimp the bullets
Just reduce your powder charge and you'll be fine. It happens that max load data can be too much for your rifle, hence the recommendation to start low.

It only takes a few rounds to find the pressure limit safely.

Load 4 rounds from 33.2 - 36.2 and see what the pressure looks like before loading a few to shoot groups.
 
I know it doesn't make much sense, but if you look at the one below, the range is from 29.3 to 35.2 but for the Noslet. If I was load developing, I tend to start less than the max weight for similar weight to be on the safe side. As others have mentioned, start at 33.2 and do .5gr increments and would definitely stop at 37gr. I have a feeling, you might find your reliable load within that range.

A formula I use is usually is 20% of (Max Weight - Min weight) added to the min weight. So for your load it would be 39.4-33.2 =6.2 gr x .2 = 1.24. Add this to the min load 33.2+1.24 = 34.44, which is usually around where you might hit the sweet spot. I was told this by an acquiantance and usually do a -.5 gr/ control/ +.5 gr / +1gr when developing loads. This usually falls within the safe zone and limits the number of rounds I need to load to get started. Just my view and I have started reloading only last year but does get some accurate results. As others have mentioned, start low and work the load up and any notice of pressure signs, stop immediately.


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Many thanks Arunt i never looked at the 85 gr Nosler data strange how it differs. i am loading some as i type and will give it a go 👍 👍
 
Thanks Andy that was my next port of call .. been in contact with a guy i shoot with who has one. Be interesting to see the results from each load and also my 80 gr & 100 gr Sierra lead loads.
 
I find that Barnes tsx reach velocity in my rifle (.375 300gn) with a good deal less powder than an equivalent lead bullet. It spooked me the first time. Start low and you'll be fine.

PS as @Andyquadra says, use a chrono: removes a lot of the guesswork.
 
Cheers Carl will do. I am a little worried as it popped the primer out at 37.4 gr ... What will it do when i start lower 33.5 gr 34.5 gr & 35.5 gr that i have just loaded ?
 
Hi All
Loaded my first lead free & shot them this morning , the.308 Fox 150 gr were spot could not be improved on accuracy wise however the .243 Barnes tsx were spread across 4 inches no pressure signs , overall length 2.645 used as barnes loading data suggested. 37.5 gr N140 a grain short of the max load . Will now try the ' Jump' as per barnes instructions starting at 50 thou & widening at 25 thou increments up to 200 thou.
The rifle is a Sauer 200 more than 30 years old with a certain amount of freebore where metal used to be but it will shoot normal 100gr loads to sub 1/2 moa. Any helpful polite suggestions please.
 
Is the added bullet length compressing the load?
As far as I am able to ascertain the load is slightly compressed , the last cannelure before the ogive is bisected by the case mouth , may have to try a denser powder to enable the bullet be be seated slightly deeper. I have always used standard
powder loads normally a grain under max as given have no knowledge of compressed load problems. , have you an idea the compressed load causes flyers
 
Reloading is a dark art I find and it pays to think outside the box sometimes.
I am assuming the bullets you are using are non toxic which will mean they have to be longer to get the same weight as a lead bullet.
I am no expert to be sure but play around a bit and see if you can improve matters with different powders etc
 
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