I agree with Iowa:

I think $40 accomplishes the same thing if not more.
The pot's about $50, so maybe $48 or something. The allin is a bluffier bet than $40, or $48 and many players are more likely to call it.

If he's not got enough to call he'll probally fold either way. If he's got the nuts he's calling either way. If he's facing a tough choice then villains more likely to lose control and call outta frustation to allin then near pot-size (which is virtually allin, anyhow).

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I think your play's a winnning play, but unecessary. One reason I could find for it...

I hope you showed your cards, and then allined the nuts later.