[Boatanchors] [Glowbugs] Bird 50Ω milspec dummy load measuring @ 56Ω's?

[Glen Zook]

Unless you are making measurements for clients who have very strict tolerance requirements, being 56-ohms won't make a hill of beans difference for amateur radio purposes!  Methinks you need step back, get a cup of coffee, tea, etc., and then hide your ohmmeter!

 Glen, K9STH 
Website: http://k9sth.net

      From: Howie WA3MCK <wa3mck at gmail.com>
 To: Boatanchor group <boatanchors at mailman.qth.net>; Glowbug Tetrode <tetrode at googlegroups.com>; QRP-L Mailing List <qrp-l at mailman.qth.net>; "njqrp at yahoogroups.com" <njqrp at yahoogroups.com> 
 Sent: Monday, July 10, 2017 4:14 PM
 Subject: [Glowbugs] Bird 50Ω milspec dummy load measuring @ 56Ω's?
   
Gang,
I have a Bird 80 watt dummy load, with sealed oil chamber (accessible via drain plug) and heat radiating fins, that is spec'd at 50Ω.
I have measured the D.C. resistance with several reliable ohm meters at 56Ω. So it's drifted up over the years...
As we used to say in the "Canoe Club" (USN) it's testing "high out of spec" - a bit over 10%.
Recommendations? Comments? Is it on the way out or am I being too picky?
It's been in service here for years. It's never been abused. I have hit it with about 90 watts on occasion for s few seconds although I doubt that would have caused the upward drift.
Could use your collective advice! 
Thank you de Howie WA3MCK