300 rum doing something new.........

[Outfall]

Ok so here is the deal, same rifle same loads and now the primers seem.to be cratering??? the only thing that has changed is this is a new brick of cci large rifle magnum primers. same brass, same bullets, same powder. they shoot the same but want to see what you may think of why this is now happening. could it just be because its a new batch of primers? the rounds were loaded and finished off the previous brick so time to reload and i opened a new brick. remington nickle brass on 2nd reload, norma brass on first reload.

 

[orkan]

When is the last time you cleaned your bore?

Different lot numbers of primers will often be different, sometimes drastically so.

-----------
Follow on Instagram
Subscribe on YouTube
Amazon Affiliate

 

[Outfall]

When is the last time you cleaned your bore?

Different lot numbers of primers will often be different, sometimes drastically so.

-----------
Follow on Instagram
Subscribe on YouTube
Amazon Affiliate

I clean it everytime before and during and after i shoot. it is very clean.

 

[orkan]

I clean it everytime before and during and after i shoot. it is very clean.

Did your velocity stay the same?

If it did... then you're just dealing with lot to lot variance. Apparently that lot has softer cups.

If you picked up velocity (which is very possible) then you're running into pressure issues and need to redo load work.


-----------
Follow on Instagram
Subscribe on YouTube
Amazon Affiliate

 

[Outfall]

Did your velocity stay the same?

If it did... then you're just dealing with lot to lot variance. Apparently that lot has softer cups.

If you picked up velocity (which is very possible) then you're running into pressure issues and need to redo load work.


-----------
Follow on Instagram
Subscribe on YouTube
Amazon Affiliate

everything stayed the same velocity and accuracy. just wondering if i should shoot the others or pull them apart. bolt lifts beautiful and no real idea of what happened lol. the powder is even out of the same jugs. retumbo on the nickle brass and magnum on the norma.

 

[Fotis]

I would not worry.

 

[Dmagna]

I clean it everytime before and during and after i shoot. it is very clean.

That could be a problem, if you left residue in the chamber it could cause a pressure spike. Also if some rifles don't like clean bores, need to leave the carbon in them until the accuracy fades.

 

[Fotis]

I have a batch of federal 215's that do this from starting loads to max in my Weatherby's. Velocity is a by product of pressure. To a degree you can't have one without the other. If you're not seeing velocity spikes that dog is good to hunt.

 

[Coldfinger]

Generous firing pin hole in bolt face? They don't look too bad to me still bevel showing on outside of primer.

 

[Outfall]

Generous firing pin hole in bolt face? They don't look too bad to me still bevel showing on outside of primer.

factory bolt face only about 200rnds on it never did it before

 

[Outfall]

im shootin: 176 atips and 178 amax.

176 atip
96.5gn magnum powder
cci lrmp
norma brass 3.7col
+/- 8fps of 3200
groups around 1/3 moa

178 amax
92.6gn retumbo
cci lrmp
remington nickle brass 3.7col
+/- 13fps 3200
groups just over 1/3 moa no matter what i do
devestating on deer and hogs

same loads ive run in this rifle and the other which is now a 338 edge

just didnt want to have a major failure and it made me wonder as it never happened before

 

[Coldfinger]

If your bolt isn't stiff opening I don't see anything to worry about

 

[DUSTY NOGGIN]

im gonna go with its warmer than last time you shot em

i bet if you shoot a factory round and it will do the same to the same extent

since you dont have any other pressure signs on the case head ,id call it good unless it blows a primer at that crater

your firing pin hole has been the same size , id guess it just didnt stand out to you before but was still present., you can have it bushed from a place like THIS

 

[Outfall]

im gonna go with its warmer than last time you shot em

i bet if you shoot a factory round and it will do the same to the same extent

since you dont have any other pressure signs on the case head ,id call it good unless it blows a primer at that crater

your firing pin hole has been the same size , id guess it just didnt stand out to you before but was still present., you can have it bushed from a place like THIS

i never did notice it before and i usually dont miss much but thats not to say i didnt miss it for sure. as far as the temp it was actually a hot day as this time of year central florida is hot and humid as can be. last time i shot was only a couple months ago so yes it could have been a little cooler. thanks for the bolt bushing tip i had never thought of it or even knew it could be done lol. thats why im here and asked, everyone is great here and there is a wealth of knowledge to be shared and learned. thanks