Is there a suggested weight limit for this pack? I am going to Philmont with the Boy Scouts this summer. We are thinking ~40 lbs of gear. The pack I have been training with is both old and heavy.
Belrix40 lbs is probably a little high for any long period of time. This pack prefers to be fully loaded at or below 30 lbs. If you are wanting to have a higher load capacity I recommend the Blaze AC 60. With it's thicker hip belts and shoulder straps and molded plastic framesheet, it provides a better carry for weights above 30-35 lbs for a modest weight penalty of about 10 oz (compared to the Crown). I actually have both packs and love them both equally but for different reasons.
BelrixIf you have not already, check out
http://sectionhiker.com/lightweight-scouting/
He mentions and links to an article by Doug Prosser. Prosser was able to eventually do Philmont with sub 15 pack weight. There are quite a few ways you can get your weight down, such as using your own tarp, a different bear line, and better cooking equipment and methods, and better tents. Philmont issue equipment is made for Scouts who are going their first/second time and who don't know what they are doing. It's Scout-proof. And weighs an appropriate amount.
Doug's old, somewhat dated article is still useful. https://backpackinglight.com/boy_scout_gear_list_philmont/
Read up. You should be able to go way under 40 lbs. Almost everything is newer, lighter, and better than what I carried in the 70's. Except my MSR gas stove. Penberthy made good stuff.
After one of our Scouts had a bad time with ancient equipment, one dad said "Well, it's what I used to use." I replied that he didn't come to the Troop meeting with a horse and buggy. That got the message across.
For big three, done pretty cheaply and pretty light: Klymit sleeping bag, Granite Gear pack, Tarptent (by Henry Shire). There are others also.