LHBS does not have Horizon. Im brewing an IPA and it calls for .75 oz. horizon @ 60 min. For bittering 28 IBU. I searched online and came up with magnum as a substitute.
What do you all suggest/recommend?
Hop substitutions
Moderators: BlackDuck, Beer-lord, LouieMacGoo, philm00x, gwcr
Re: Hop substitutions
All the charts I use for subs show the same, Magnum. But, I've used Warrior to sub for Magnum before, so.........? 
PABs Brewing
Re: Hop substitutions
Magnum or Nugget could / would be acceptable substitutes. ( and Warrior or even Target I suppose...)
Be advised that although Horizon has a pretty high Alpha Acid content, it has a lower Cohumulone percentage which is what makes its bitterness so smooth.
So, even if the alpha acid content of your substitute is the same as the Horizon, it will be perceived as more bitter for the same amount of hops over the same time.
I would at least use some brewing software and recalculate using the revised hop...
Moreover, since the substitute hop would most likely have a higher cohumulone percentage, I would consider adding it later in the boil rather than earlier (boil for less time) and using to software to choose an appropriate amount of it for that later addition. That should soften the bitterness profile.
Hope this helps...
Be advised that although Horizon has a pretty high Alpha Acid content, it has a lower Cohumulone percentage which is what makes its bitterness so smooth.
So, even if the alpha acid content of your substitute is the same as the Horizon, it will be perceived as more bitter for the same amount of hops over the same time.
I would at least use some brewing software and recalculate using the revised hop...
Moreover, since the substitute hop would most likely have a higher cohumulone percentage, I would consider adding it later in the boil rather than earlier (boil for less time) and using to software to choose an appropriate amount of it for that later addition. That should soften the bitterness profile.
Hope this helps...