Please listen to other’s response to this. There is a wealth of information that is available to answer your question.
I have zero experience with Magnus heads but I hear they do very well on deer, like 99% of broadheads do.
The additional weight will definitely help with penetration BUT in doing so you must keep the arrow flying perfectly to reap the penetration benefits.
So..depending on the arrow spine you are currently using the 175 grain head you mentioned may or may not allow your arrow to fly as well as it should. The heavier weight tends to weaken the arrow.
That is my answer in a nutshell but again listen to what others hear tell you and read the Ashby reports in the “Ashby Library” up top.

Richie

Shooting wood arrows accurately and lethally every time is a learning process that you can shortcut with good advice, but which still requires personal experimentation and experience. I’m think mostly here about the spine question. Assuming you have a correctly spined wood shaft, you can stack on a lot of weight up front. It will predictably make a correctly spined arrow more accurate, but also increase trajectory and cut speed. But speed don’t kill — it’s momentum, whose prime ingredient is weight. The more of that weight up front, the better. If it were me, using your current shafts that fly well at 125, I would buy a couple each of 145, 160, 190 field points and see how far you can push things without losing spine or encountering other problems. When you hit that point you can either step up the spine, or stay with the greatest weight your current shafts can handle. That said, I will wing it a bit and suggest that you try the Eclipse 145 two-blades, in either double or single bevel. They are dynamite on deer and fly great and although not “hard” by say Grizzly standards, aren’t likely to fold over on you. But play with field points first. ttf

I’ve been shooting 125-grain heads for pretty much all of my bowhunting. I’ve put them through some incredibly tough bone (exit side, as it should be), and the model of head I’ve been using for the past 7 years has never came out with even the slightest damage.

It’s not a weight issue. It may have to do with the broadhead model itself. I shot those into some targets for a couple months one year and had the same experience.

I’ve experienced the same with that head only it was in contact with bone. The arrow literally bounced off the shoulder as the tip curled. Since that time a long time ago I have learned a ton.

I don’t know what aluminum shaft your shooting but if your going to stick with a two blade I’d try stos. I have some 125’s and 160’s here that I’ve shot and played around with along with some other heads; seems I’m always trying out different heads.

Now my archery range consists of 2 bags or a foam target backed up by a bag against a cement block wall, its in the corner. The last time I tried some broadheads I was tuning a new arrow setup and of course I tested the stos, eclipse, stingers, centaur and a few different 3 blades, all 200 gr. The stos consistently out penetrated all other heads by 8 to 10″. On a few occasions the arrow went all the way through both bags and stuck itself in the block wall enough that it was tough to get out. Kinda had to pry back and forth and such. Neither time did the tip curl but the last time it did bend a bit. So I took a hammer and straightened it out, spined tested it, resharpened a bit and it was good to go. All other heads I’ve tested have generally become worthless after hitting that wall except for the eclipse. This is only the 125 gr model with a 75gr adapter and the 160’s are tougher yet. You can use inserts from 25grs on up to find the right weight that flies with your arrows so you should be able to come up with something that flies well.

Any ways, I am not a rep for stos, I just really like this head and since the season is now 5 weeks away I will be using them this yr. Next yr could be different 😀

msarcher wrote: THANKS FOR THE ADVISE, IM SHOOTING A 2117 EASTON XX78 SHAFT BUT I REALLY WOULD LIKE TO GO TO CARBON BUT IT SEEMS TO BE SO MUCH TO KNOW AND LEARN ON WIEGHTS AND INSERTS AND TESTING THAT I JUST DONT KNOW ANYTHING ABOUT OR HAVE THE TIME OR MONEY TO RUN THRU IT ALL. PLUS I HAVE ALOT OF ALUMINUM ARROWS MADE UP. AGAIN THANKS FOR THE ADVISE!

what weight bow are you shooting? whats your draw length? is the riser center cut or?

There are two basic elements that control how easily, or if, a tip will curl and/or break: One is steel hardness and I personally won’t shoot anything under Rockwell 50. The second does have to do with weight, if only indirectly, and that is steel thickness at the tip. You can only have so much steel and hold the weight to 125. Thus, the heavier the head, the thicker the steel can be and usually is at the tip, especially if the head is long and narrow, as per Dr. Ashby’s advice. While Eclipse steel is usually in the high 40s (unless Blake has upped it since I visited his one-man factory), their two-blades are reinforced at the tip and also have a rather wide tip, which provides more strength. I also love STOS heads and have killed several elk with the 160 without ever a failure. dp

Assuming your arrow is 29″ long and you draw 28″? You should be able to shoot a 175 or possibly a 200 grain, with insert, head. foc is 16 to 18% and the weights up over 560 which will help penetration.

Msarcher -= Ashby is adament about never using aluminum adaptors, and they provide a very weak link in the system with a high failure rate. You can get steel adaptors down to 75 grains. In all such cases my advice is to spend the small amount of money involved in buying an assortment of heavier target points — several suppliers offer “sample sets” of one or two points in a variety of weights — same with inserts, adapters, etc. and find out the max weight your rig can shoot accurately, then back off to where you want to be. Then equate that weight with a broadhead to make sure it performs the same as field points. It’s so very cheap and easy to play with these things, I believe we all should do it as part of our annual hunting preparation. Each time I build a new dozen arrows, whether wood or carbon, I go through this procedure. dp

Dave, I totally agree with your post. My problem is pittling and tinkering to get what I think is the most lethal arrow I can build…and then NOT stopping there.
I could be a charter member of “Arrow Scientist Wannabe Anonymous.”

msarcher,

You’re shooting fairly close to what I’m shooting. I shoot 60# at 29 1/2″, and I cut my arrows (2117 xx75’s) at 31 1/2″ with a 145 gr. field tip and 150/160 grain broadheads. My finished arrow is somewhere around 585 grains. I don’t know how much arrow you want out in front of your riser, but with 175 grain tips, you could probably get down around a 30 to 30 1/2″ arrow, and a heavier tip would get you a bit shorter. Just hafta play with it a bit. I’m looking at possibly going to a heavier tip, as well, at some point. Good luck, hope this helps some.

Michael.