Ok ill try and keep the premise simple. If you have 1 lot of brass, but they are sized differently how will this effect accuracy and load workup?
For example. Measuring from the base to a point on the shoulder. You have some cases sized at 1.180 and some sized at 1.188. The shoulder is set back 0.008 further on the first batch.
To my understanding this would reduce case capacity affecting the way the powder burns?
The case stretch during firing would also cause a change in case volume during firing reducing pressure and creating inconsistancy?
Reason i am asking. I have an overly roomy chamber in a rifle. I will be adjusting my dies for a 0.004 shoulder set back to try and increase consistency, improve brass life, and reduce trimming. I started out with factory ammo which i can size properly now. However i just received 250pcs of new starline brass which is coming in shorter. Im concerned that if i try and work up a load with this brass, and then size it to more appropriately fit the chamber, it may effect the load workup i did with the smaller brass, both in velocity and accuracy. I really dont want to burn the components, 250 rounds, trying to do fire forming.
Im fairly certain the size difference will have an effect. The question is, how much, and what if anything should i do about it.
For example. Measuring from the base to a point on the shoulder. You have some cases sized at 1.180 and some sized at 1.188. The shoulder is set back 0.008 further on the first batch.
To my understanding this would reduce case capacity affecting the way the powder burns?
The case stretch during firing would also cause a change in case volume during firing reducing pressure and creating inconsistancy?
Reason i am asking. I have an overly roomy chamber in a rifle. I will be adjusting my dies for a 0.004 shoulder set back to try and increase consistency, improve brass life, and reduce trimming. I started out with factory ammo which i can size properly now. However i just received 250pcs of new starline brass which is coming in shorter. Im concerned that if i try and work up a load with this brass, and then size it to more appropriately fit the chamber, it may effect the load workup i did with the smaller brass, both in velocity and accuracy. I really dont want to burn the components, 250 rounds, trying to do fire forming.
Im fairly certain the size difference will have an effect. The question is, how much, and what if anything should i do about it.
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