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Rifles, Reloading, Optics, Equipment
Reloading
Quickload and 6.5SS
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<blockquote data-quote="jb1023" data-source="post: 1500764" data-attributes="member: 91995"><p>Just a quick update on my findings. I have not measured my cross-sectional bore area and at this point I don't plan to. I played with some different measurements and it has very minimal impact on vel or psi so I don't think it is worth the effort, the default should be close and quite frankly I don't have the tools to get anymore precise. I pulled an unfired bullet from the same batch that my actual velocity was measured from and these are the measurements:</p><p>Barrel:</p><p>Mark Chanlynn</p><p>Barrel length: 24"</p><p>4 groove cut rifling</p><p>lil beast 3 port break</p><p></p><p>Round:</p><p>COAL: 2.925</p><p>Hornady ELD-M 147</p><p>Bullet length: 1.439"</p><p>Bullet weight: 147.22gr</p><p>Case length: 1.950"</p><p>RE26: 58.4gr</p><p>***Might need a new scale as the original loaded weight was 58.5 but the pulled weight was 58.4 and I'm pretty sure .1gr did not just vanish.</p><p></p><p>Average velocity from 5 fired rounds over Labradar: 3187 </p><p>***Different from yesterdays post because I pulled a 58.5 round apart whereas yesterday I used 58.0 data for the post.</p><p></p><p>So the base Velocity (with all physical measurements input that I am capable of inputting) is: 2938</p><p>and the base PSI is: 55705</p><p></p><p>I decided I would change the Ba by a <strong>maximum</strong> of +/- 10% as that is the number that is displayed in the notes at the bottom of the QL graph. So for RE26 the default is .3397, I added 10% to that and got .3737 (rounded up as QL will only accept 4 digits). </p><p>New velocity is: 3057</p><p>New PSI is: 68979</p><p></p><p>I found out that the weighting factor is a guestimate of how much powder is expelled from the case into the barrel where it subsequently burns, or doesn't. A 0.0 would mean no powder gets expelled and it all remains in the case. The default for the 6.5 RSAUM is .5. If I dropped that to .18.</p><p>New velocity is: 3164</p><p>New PSI is: 61009</p><p></p><p>This combo puts my predicted velocity within the average I actually saw on the range. In my head I am able to justify the Ba adjustment because that is clearly listed on the QL graph so it is a variable. The weighting factor makes sense, in my simple mind, because the SS is more efficient than the SAUM. Another factor that makes sense to play with is the Shot Start PSI. I opted not to change this though because I am loading .020-.040 off the lands and am not using any sort of lubed projectiles.</p><p></p><p>Thoughts on my new thinking?</p></blockquote><p></p>
[QUOTE="jb1023, post: 1500764, member: 91995"] Just a quick update on my findings. I have not measured my cross-sectional bore area and at this point I don't plan to. I played with some different measurements and it has very minimal impact on vel or psi so I don't think it is worth the effort, the default should be close and quite frankly I don't have the tools to get anymore precise. I pulled an unfired bullet from the same batch that my actual velocity was measured from and these are the measurements: Barrel: Mark Chanlynn Barrel length: 24" 4 groove cut rifling lil beast 3 port break Round: COAL: 2.925 Hornady ELD-M 147 Bullet length: 1.439" Bullet weight: 147.22gr Case length: 1.950" RE26: 58.4gr ***Might need a new scale as the original loaded weight was 58.5 but the pulled weight was 58.4 and I'm pretty sure .1gr did not just vanish. Average velocity from 5 fired rounds over Labradar: 3187 ***Different from yesterdays post because I pulled a 58.5 round apart whereas yesterday I used 58.0 data for the post. So the base Velocity (with all physical measurements input that I am capable of inputting) is: 2938 and the base PSI is: 55705 I decided I would change the Ba by a [B]maximum[/B] of +/- 10% as that is the number that is displayed in the notes at the bottom of the QL graph. So for RE26 the default is .3397, I added 10% to that and got .3737 (rounded up as QL will only accept 4 digits). New velocity is: 3057 New PSI is: 68979 I found out that the weighting factor is a guestimate of how much powder is expelled from the case into the barrel where it subsequently burns, or doesn't. A 0.0 would mean no powder gets expelled and it all remains in the case. The default for the 6.5 RSAUM is .5. If I dropped that to .18. New velocity is: 3164 New PSI is: 61009 This combo puts my predicted velocity within the average I actually saw on the range. In my head I am able to justify the Ba adjustment because that is clearly listed on the QL graph so it is a variable. The weighting factor makes sense, in my simple mind, because the SS is more efficient than the SAUM. Another factor that makes sense to play with is the Shot Start PSI. I opted not to change this though because I am loading .020-.040 off the lands and am not using any sort of lubed projectiles. Thoughts on my new thinking? [/QUOTE]
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