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#123730 - 11/12/09 05:31 PM Backpack sizing
Rdljr Offline

Registered: 11/06/09
Posts: 14
Loc: NH
My currnt backpack a Kelty 3000 wieghts in at 74 oz and the website says 3000CI. In looking for a lower wieght pack I have noticed that all of the internal frame packs in the 3000CI size range do not look like I could fit the same amount of "Stuff" in/on them. I attach 2 compression bags on the external part of the fame with volumes of 10 LT (600CI) each. So am I correct that I need to look for a 4500CI+ internal frame pack to achieve the same carring capacity? If that is true do you realy save any wieght by switching to an internal frame pack or is that more of a comfort thing?

#123742 - 11/12/09 07:13 PM Re: Backpack sizing [Re: Rdljr]
Zalman Offline

Registered: 10/25/09
Posts: 97
Loc: Olympic Peninsula, Washington,...
Originally Posted By Rdljr
So am I correct that I need to look for a 4500CI+ internal frame pack to achieve the same carring capacity?

You can comfortably strap quite a bit more onto the outside of an external frame pack than you can to an internal framepack. But you can still strap some amount of stuff to an internal frame pack too, so you'll need a larger volume capacity inside, but maybe not quite that much larger.

Originally Posted By Rdljr
If that is true do you realy save any wieght by switching to an internal frame pack or is that more of a comfort thing?

My experience is that the typical internal frame packs (Osprey, Gregory, etc.) are significantly heavier than their external frame counterparts. Their advantage is that they hold the weight of your load close to your body, which makes the whole bundle feel lighter on your back.

However, there are lightly framed or unframed packs that are much lighter than typical internal frame packs, such as the Vapor series from Granite Gear, GoLite packs, etc. These will typically save you quite a bit of weight over an external frame.
It's easy to be a holy man on top of a mountain.
-- Larry Darrell

#123806 - 11/14/09 10:10 AM Re: Backpack sizing [Re: Zalman]
phat Offline

Registered: 06/24/07
Posts: 4107
Loc: Alberta, Canada

What he said.. excellent reply Zalman.

I'd only add that many people switch to internal frame because "that's what the cool kids carry" so it's partly a style thing too.

If you really want to start looking at a lighter pack, look at what you're carrying in it first. lighten up your pack last - so that you buy a pack that is the right size and the right amount of support for what you are carrying *in* the pack. If you were to for example, buy my usual pack (frameless Granite Gear Virga) and then stuff 40 pounds of stuff in it - you would be very uncomfortable! even though the pack is VERY light (580 grams for the pack!)

I still use my big honkin 7 pound packs for carrying big loads, on the rare occasions (usually winter) that I do.

Any fool can be uncomfortable...
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#123829 - 11/14/09 06:56 PM Re: Backpack sizing [Re: Rdljr]
billstephenson Offline

Registered: 02/07/07
Posts: 3917
Loc: Ozark Mountains in SW Missouri
You two can correct me if I'm wrong, but they way I understood it is that external frame packs are better on the trails, and internal frame packs better off trail. If that's true, than you'll want one for the type of hiking you'll be doing most.

I have a small "Peak" internal frame pack that I use for long day hikes. It is more comfortable off trail and it tends to get caught up less in branches and brush, but it's smaller with lighter loads than my external frame pack that I use for longer ventures into the forests so I can't really compare them.

The people I know that use newer, larger, internal frame packs say they like them a lot.

phat has it right too. Tinker with your gear and gear list to lighten your load first. Then get a lighter pack to fit it. (I still haven't done the latter wink

I have to add this too, after reading some recent posts here about people doing several nights out of a day pack, I think I'd like to try and see if I can fit an overnighter into my smaller pack and work from there. I was really inspired reading about that. I seldom go out for more than 3 nights and I think I have everything I really need to pull it off.

#123837 - 11/14/09 09:19 PM Re: Backpack sizing [Re: billstephenson]
OregonMouse Online   content

Registered: 02/03/06
Posts: 6769
Loc: Gateway to Columbia Gorge
I agree with Bill and phat. Get the rest of your gear list where you want it, measure it (those plastic storage bins are good for approximating, since the bin's tag usually shows how many liters the bin contains, and there are approximately 60 cubic inches in 1 liter) and buy your pack last. Be sure to include the equivalent weight and bulk of food, fuel and water for the maximum time you expect to go out. Load up the new pack to be sure everything fits inside, and then "hike" around the house with it for several hours. If you're getting the pack at a store, take all your gear with you when you go and do the "hike" in the store (do a lot of going up and down stairs if you can).

Be sure that your total pack weight (including pack) does not exceed the maximum carrying capacity for the pack in question (usually found on the manufacturer's web site). In fact, total pack weight should be at least five pounds under that maximum. A 10 pound margin would be better if you're going to be in desert areas (that's 1.25 gallons of water).

My own experience with external vs. internal frame packs is that the external frame has a life of its own, often zigging when I zag. I've had several falls as a result. The internal frame, on the other hand, moves with me and very rarely pulls me off balance. There was the time when I didn't duck low enough when going under a leaning tree, and ended up sitting down abruptly (just missing my dog) when the pack caught. Except for that episode, I haven't had the balance problems I used to have with the external frame.

Edited by OregonMouse (11/14/09 09:21 PM)
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

#123859 - 11/15/09 12:31 PM Re: Backpack sizing [Re: OregonMouse]
balzaccom Offline

Registered: 04/06/09
Posts: 2109
Loc: Napa, CA
Great answers here. My wife and I have an old external frame pack that is 30+ years old, and a relatively new pair of internal frame packs. The weight is identical for each pack. And I am not sold on the (put everything in one sack, which makes is harder to dig out later) newer designs.

But our sleeping bags and tent are new, small and light. So small that they don't strap conveniently to the outside of the external frame pack.

Still, I have seen WAY more people carrying too much weight, and too much stuff, because they have a large pack and managed to fill it.

And we don't seem many people who are under-equipped because of a small pack...just happy people with less weight.

Edited by balzaccom (11/15/09 12:33 PM)
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