9mm 124gr vs 125gr

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bbqreloader

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Curiosity, I can find load data for 700x for 125gr, but not for 124gr, Xtreme plated FP. Is the 1 gr difference a deal breaker or could I go with the start min for the 125 if I am using the 124?
 
I interchange 124 and 125 gr bullet load data without issues.

Weigh some bullets.

Many jacketed bullets vary by 1+ gr, plated bullets vary by 1-3 gr+ and lead bullets by several grains. ;)
 
I have done this for my 9mm rounds. Start low and work up! I typically use RMR thick plated which can be loaded using FMJ data up to 1500fps but I still start in the lead range and work up until I find a load that cycles my gun well and is accurate.
 
1 Gr difference in weight of the same type bullet (Plated, jacketed, lead, coated), is insignificant.
 
The load data from Hodgdon is for the Berrys hollow base round nose-tp. However LEE's data has 3.0 for the 125 grain jacketed. Since the Xtreme it is not a hollow base I was considering that start load with the Lee data, was not to sure if the one grain diff was a powder issue. I just did email Hodgdon support to see what they say. I also have no intention to get close to the 1200fps limit anyway, just plinkers, wanted to use up the powder. Thanks for the replies so far!
 
The one grain difference will make no difference. What will make a big difference is how deep they are seated. I've loaded the Xtreme 124gr FP and I've needed to load them deeper than 124gr RNs in order for them to chamber in my pistols. What I mean is how deep the base of the bullet is in the case, which will determine case capacity and will have the biggest impact on pressure. The FP seated to the same depth as a RN will have a lot of the shank of the bullet out of the case and at least in my pistols will not pass the plunk test. With the FPs seated deeper I had to reduce powder charges to keep pressures safe. Start low and work up carefully and use a chronograph if you can.
 
As likely stated, case volume after bullet seat and bullet construction will have a far greater impact on pressure.
 
BDS makes a valid point, most bullets will have at least that much weight variation to begin with.

Specifically referring to 9mm, I've used 125 gr data with 124 gr. bullets for as long as I can remember, no issues here.

But when the weight variation starts getting more significant, I then generally work up using data for the next heavier bullet.

BTW, a 1 grain weight variation in this case, is less than 1%.

GS
 
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