Strength of alum insert on carbons??

[KSdan]

Can anyone tell me of experience with standard aluminum inserts in carbon shafts.  I have been using brass but may need to go to steel adapters for a new broadhead configuration. I will need to drop down to alums for the wt. Are the alums as strong as the brass? Does the steel adapter screwed into the alum adapter make it more bomb proof? I am trying to come up with a bomb proof bone breaking combo.

Thanks
Dan

[Piratkey]

The aluminium used in insert are less strong (strenght) than brass, But ,for me;in this case, the weakess part come from the carbon shaft and not because the aluminium insert is more weak than brass.
It's usually "bomb proof" with brass insert because this one is more long,that's all.
With a shorter aluminium insert if you want somethink very strong you have to use external footing,but this add weight .
Find same lenght alu insert than you brass insert and that's could be good

[COOCH]

No the aluminum insert is much softer and more prone to mushrooming than the brass.I have taken the brass adapters and cut them in half to decrease the weight.

An external aluminum foot of about 1" or so also really helps to strengthen the front of the arrow  and prevent splitting on heavy impact hits.

[JimB]

I believe,and I'm going on memory here,Doc Ashby said the steel adapter with aluminum insert gave more strength than vice versa.I won't shoot any carbons without aluminum footings and that would strengthen the area around your aluminum insert tremendously.It will only add 10-12 grs for 1".

[Doc Nock]

I'm with Pirate and Cooch.

There were some steel adapters that were faulty but now that is "fixed" and I'm told, there are better grade aluminum arrow inserts and tempered Alum adapters, according to some.

Regardless, the shaft, would seem to be, the weakest link. While Cooch is comfortable with a 1" "over-foot" of aluminum shafting, I prefer 3". Shooting GT's, I'm using 2117 over foot of 3" and just heat a hot melt stick and while sticky...dab onto the GT shaft...then heat the 3" over-footing (beveled (chamfered) on both ends w/ a reloading neck tool) and then slip over the shaft. It melts the hot melt and then I turn it around and around and move up and down some to distribute the hot melt evenly.

Dip in cool water to set.  Then put in whatever insert!

I (inadvertently) hit low on a shot at a gator that I "thought" was on a moss covered log (3D shoot) but was a moss covered ROCK! It destroyed the field tip, but the shaft was untouched! That cynched it for me to have the overfooting.

[KSdan]

Thanks guys.  I have also read somewhere here over the past year or so of someone (?) who was putting glue down the inside of the shaft "behind" the insert.  The glue created a "shoulder" behind the insert distributing the impact pressure down the entire shaft instead of the shoulder where the insert meets the shaft edge.  Make sense?  Wish I could revisit those threads- someone really made some heavy bomb proof arrows for Australia, Africa or somewhere like that. Anyone recall??

[AdAstraAiroh]

Dan,

If you purchase the Carbon Express Bulldog nock collars to fit your shaft O.D. and epoxy them on the point end of the shaft before you glue in an aluminum insert they make the arrow nearly bombproof.  The bull dog collars actually fit over the top front edge of the arrow shaft slightly and distributes the shock of a hard impact over its entire length. Additionally, depending upon your shaft size, it only adds 4 to 6 grains to you point weight, and they cost about $8.00 per dozen.  

Mark

[Ringneck]

As stated the weakest part is going to be the shaft right behind the insert. I would rather have the extra strength and weight in the broadhead adapter than the insert.

[COOCH]

I've been meaning to do a build along on this very subject,however time has been a rare commodity as of late.I have had amazing results with an internal parabolic wooden dowel,brass insert,steel adapter,aluminum over foot,and a solid steel broadhead. I personally lean toward the big 190 grain grizzly el grande, but I have a bunch in the stable.

If your looking for a truly bomb proof bone breaking set up forget about aluminum inserts or ferrules they are the notoriously weak link.

[JamesKerr]

If you are looking to penetrate heavy bone, than you need to use a brass insert and a steel broadhead adapter. Also, your arrow needs to weigh atleast 650 grains.

[KSdan]

Thanks guys.  JamerK- I realize 650 was Dr. Ashby's study with heavy African bone.  But whitetails ??  I am shooting 550gr from 53# Black widow, 30+" draw, 20% foc.  Sure seems like enough. . . maybe not.

Dan

[COOCH]

The one way to find out is prop a critter up after killing and purposely shoot the big bones.I think you'll find your a tad on the light side.Once I started shooting 700ish grain arrows I saw a huge difference in penetration on bone.

Bone is Bone it matters not weather the critter lives in America or Africa.

[Doc Nock]

Speaking with Dr. Ashby a time or 3, I got the distinct impression that his recommendations were only the compilation of years of testing he did and trying to be consistent in what and how he did what he reported to provide at least vigor to his research if not statisical power.

I never heard him be autoritative and state one MUST do this or that...only that he was representing the criteria of his research accurately, and any variation from that, he personally could NOT attest to what difference it might make in outcomes.

I think that is important to note.

I can say that my understanding would be that 20% is on the low end of EFOC. I also know from working with friends that BW,(recurves anyway) like my Morrison, is cut WELL PAST center...so that it takes a stiffer arrow, as did mine.

That meant getting more gpi than I wanted and lowered my FOC as the overall weight was in the shaft.

I shimmed out my sideplate a bit till I showed "stiff" on my chosen arrows and then could up my point weight.

None of this is rocket science NOR is it REQUIRED.  As Cooch says... bone is bone.

When things go right, obviously, those light weight "expandable" heads work ---as lots of critters are killed by wheelie folks with them.  Every thing in between the extremes will WORK...and consistently, so there is no holy grail of right or wrong!

When things go wrong, and they will, (at least in my Murphy-driven world)    I like to have every flipping thing  I can employ on my side working to make a clean(er) kill...whether it be a rabbit or a buffalo!

[COOCH]

"When things go wrong, and they will, (at least in my Murphy-driven world)  I like to have every flipping thing I can employ on my side working to make a clean(er) kill...whether it be a rabbit or a buffalo!"

Doc hit the nail on the head that is how I see it. If all goes well no worries,BUT, when they don't I want every advantage on my side that I can employ.

[KSdan]

Thanks guys.  Sure appreciate all the input. Got me thinking. . .