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bowhunter-tw

Are loads really bullet shape dependent??

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Yes they are. Different brands/projectiles of the same weights will shoot differently. Even identical components of a different lot number can/will shoot differently. 

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You're asking a very broad question. It's best to use that bullet's manufacturer's reloading data. Todays manufacturers all have reloading data available on the internet. There's no substitute for load testing in your rifle. What works in your buddy's rifle isn't going to work the same in your's. And don't think that you can substitute bullets in your old load either cause you can't find the old bullets you used to load in it!

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Even the same projectiles with different lot numbers will be different. 

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24 minutes ago, L Cazador said:

You're asking a very broad question. It's best to use that bullet's manufacturer's reloading data. Todays manufacturers all have reloading data available on the internet. There's no substitute for load testing in your rifle. What works in your buddy's rifle isn't going to work the same in your's. And don't think that you can substitute bullets in your old load either cause you can't find the old bullets you used to load in it!

This is why I was asking, same charge, same weight bullet, different ogive and had pressure signs on one not the other (or atleast I think pressure signs) seeing ejector swipes

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Very good learning experience and very observant on your part!! There are only two ogives on the market. While Berger contends their hybrids are actually a blend of the two, secant and tangent, it's a tangent (I know Brian Litz is going to disagree with that! LOL) A secant ogive moves the nose of the bullet back from the lands while a tangent ogive moves it forward closer to the lands. A bullet seated closer to the lands can multiply the pressure exponentially! Over pressure puts needless wear and tear on the brass and your rifle's action! Start a new load. You may see the best load ever for that rifle! How do you tell secant from tangent? The secant has a sharp pointed nose where the tangent is more curved and gradual. 

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22 hours ago, bowhunter-tw said:

Interesting though the secant had higher velocity for same charge

that's possible depending where you were at in relation to ogive to lands. Did you strip the bolt and measure lands to ogive?

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On 10/14/2022 at 6:51 PM, L Cazador said:

that's possible depending where you were at in relation to ogive to lands. Did you strip the bolt and measure lands to ogive?

What do you mean by strip the bolt? 

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Your question is very broad. 
 

in general if you have similar construction and similar profile the psi will be fairly close. 
 

L Cazador is spot on in it comments about psi increasing and the ogive approaches contact with the lands.
 

There are also a whole bunch of factors than can change your psi: different powder lots, different brass weight, ambient conditions, etc. you need to be more specific in your test parameters.  

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I recently got a suppressor and all the load development was done pre suppressor. I am thinking the suppressor is adding back pressure and pushing my load over pressure. 
 

does this sound plausible?

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29 minutes ago, bowhunter-tw said:

I recently got a suppressor and all the load development was done pre suppressor. I am thinking the suppressor is adding back pressure and pushing my load over pressure. 
 

does this sound plausible?

Lance might be a good person to comment on this.

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You need to back off on your load for your suppressor.You can have issues  with over pressure  .You are essentially  adding  length  to the barrel  and adding  back pressure  from the can.I to will have to back down my load for my 7-08 as I developed  it before  I had the can  and now I want to run suppressed. 

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44 minutes ago, Crazymonkey said:

You need to back off on your load for your suppressor.You can have issues  with over pressure  .You are essentially  adding  length  to the barrel  and adding  back pressure  from the can.I to will have to back down my load for my 7-08 as I developed  it before  I had the can  and now I want to run suppressed. 

I was gonna drop down about 1/2 a grain, do you think this is sufficient or should I drop back a whole grain?

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