Brass Inserts & FMJs

Discussion in 'Tech Talk' started by rustednuts, Apr 5, 2017.

  1. rustednuts

    rustednuts Newb

    Joined:
    Sep 9, 2016
    Posts:
    31
    Likes Received:
    1
    Dislikes Received:
    0
    Location:
    Maine
    I'm thinking of making the switch the FMJs this season. Is anyone using brass inserts with the FMJs or do they have enough mass on their own to handle large mechanicals?



    Sent from my iPhone using Bowhunting.com Forums
     
  2. Marshhunter1221

    Marshhunter1221 Weekend Warrior

    Joined:
    Nov 30, 2013
    Posts:
    69
    Likes Received:
    13
    Dislikes Received:
    0
    Location:
    El Paso TX.
    I shoot the FMJs and use Killzone heads, fantastic combo


    Sent from my iPhone using Bowhunting.com Forums
     
  3. davidingle

    davidingle Weekend Warrior

    Joined:
    Aug 18, 2014
    Posts:
    744
    Likes Received:
    30
    Dislikes Received:
    0
    Location:
    Iowa
    They do have enough weight on their own but I would use the weights as well. Get as heavy as you can!
     
    copperhead likes this.
  4. Coop

    Coop Grizzled Veteran

    Joined:
    Nov 21, 2012
    Posts:
    3,488
    Likes Received:
    26
    Dislikes Received:
    0
    Location:
    Springtown TX
    Just pay attention to your spine. Brass inserts are nice because they bump up your FOC while adding weight, but they also weaken spine.
     
  5. Xoutdoors

    Xoutdoors Weekend Warrior

    Joined:
    Jan 22, 2014
    Posts:
    548
    Likes Received:
    11
    Dislikes Received:
    0
    Location:
    MINNESOTA
    I was told from my proshopper that it's necessary to have brass inserts. The regular inserts will do
     
  6. Dubbya

    Dubbya Moderator

    Joined:
    Jul 24, 2008
    Posts:
    3,878
    Likes Received:
    26
    Dislikes Received:
    0
    Location:
    Somewhere in, Wyoming
    Brass inserts are never "necessary" but they'll always aid in penetration, better flight down range and energy retention.
     
    TheHardWoods913 and rustednuts like this.
  7. Xoutdoors

    Xoutdoors Weekend Warrior

    Joined:
    Jan 22, 2014
    Posts:
    548
    Likes Received:
    11
    Dislikes Received:
    0
    Location:
    MINNESOTA
    I used FMJ 340s with standered inserts last fall with a 100gr g5 strikers. I shot pass through a small 8 pt that didnt die. which it was my mistake for hitting one lung in stead of two. I also had a family relative that shot a bull elk towards and through the shoulder through the butt with 85gr slick tricks with a total 305gr arrow.
     
  8. Chef Nerd

    Chef Nerd Weekend Warrior

    Joined:
    Aug 28, 2013
    Posts:
    94
    Likes Received:
    2
    Dislikes Received:
    0
    Location:
    Wisconsin
    I believe it. Shot placement is the NUMBER ONE attribute in increasing penetration!

    ...adding tip weight does help us folks who aren't the best shot...haha
     
    copperhead likes this.
  9. copperhead

    copperhead Die Hard Bowhunter

    Joined:
    Jan 6, 2014
    Posts:
    2,610
    Likes Received:
    51
    Dislikes Received:
    0
    Location:
    Apex, North Carolina
    It really depends upon you objectives and setup. I have a shorter draw length so the brass weights help me get the target weight I want as well as the target foc. Why more weight. Several reasons, quieter bow for one. Then think of this way, extreme yes but shoot a cotton ball out of a slingshot. Doesn't go far or hurt at all right. Now do the same with a steel ball bearing. Weight doe shave its advantages. Disadvantages is of course faster drop. But our passion is more about how close than how far right?

    Your setup plays a part too so need a little more info on that to provide informed input.
     
    Sota likes this.
  10. Sota

    Sota Grizzled Veteran

    Joined:
    Jun 28, 2014
    Posts:
    9,734
    Likes Received:
    121
    Dislikes Received:
    1
    Location:
    Minnesota
    Not to be unkind but anybody that would hunt elk with a 305 grain arrow including a 85 grain broad head is a fool.
     
    Dubbya and killer chill-r like this.
  11. Afflicted

    Afflicted Grizzled Veteran

    Joined:
    Apr 20, 2011
    Posts:
    5,741
    Likes Received:
    18
    Dislikes Received:
    0
    Location:
    West Palm Beach, FL
    Inserts are great to improve FOC also when using lighted nocks.


    Sent from my iPhone using Tapatalk
     
    copperhead likes this.
  12. Xoutdoors

    Xoutdoors Weekend Warrior

    Joined:
    Jan 22, 2014
    Posts:
    548
    Likes Received:
    11
    Dislikes Received:
    0
    Location:
    MINNESOTA
    Shooting a hoyt supertech 60lbs at 320fps. If it works for them on bear, deer and elk, It works. It's like you're trying to say that Indians like ISHI are fools for using wood arrows and stone heads to kill NA game over midevel knights shooting steel arrows and heads through armor and chainmail. You know what. Go set up a grill, charcoal, and ligher fluid to make some burgers or bbq ribs, and have a nice cold beer.
     
  13. Sota

    Sota Grizzled Veteran

    Joined:
    Jun 28, 2014
    Posts:
    9,734
    Likes Received:
    121
    Dislikes Received:
    1
    Location:
    Minnesota
    We are not talking about technology that was used long ago like Ishi and medieval knights, they used the best technology available at the time, I bet you the knights and Ishi used arrows that weighed more than 305 grains. Anyway your comparison is weak soup and not even close to an arguable counterpoint. I will give you extra points for being consistent.
     
  14. Rangerdan

    Rangerdan Weekend Warrior

    Joined:
    Dec 19, 2014
    Posts:
    297
    Likes Received:
    7
    Dislikes Received:
    0
    Location:
    Vermont
    Really depends on your definition of "large game". If you mean anything in North America, then yes, the FMJ's don't necessarily require any addition weight up front. I've found they have a good balance and provide great penetration out of the box.
    If you're traveling to Aus. or Africa, I suggest putting in an additional 50gr up front.
     
  15. Marauder

    Marauder Die Hard Bowhunter

    Joined:
    Aug 29, 2011
    Posts:
    1,973
    Likes Received:
    55
    Dislikes Received:
    0
    Location:
    Tomahawk, WI
    What is the difference between adding an insert or switching to a heavier BH? For example a 125 grain BH. Inserts you do get more weight I think but would you be able to go to a heavier BH and still have the advantage that inserts give you?
     
  16. Dubbya

    Dubbya Moderator

    Joined:
    Jul 24, 2008
    Posts:
    3,878
    Likes Received:
    26
    Dislikes Received:
    0
    Location:
    Somewhere in, Wyoming
    Nobody said it couldn't be done (that story is a little hard to believe but stranger things have happened), but that is a recipe for disaster. I shot an elk at 70 yards this year with a 500gr arrow, going 280fps with a 2", 3-blade Spitfire XXX and it blew through the front shoulder blade and poked through the other side.

    The main difference is that for one (you are correct) you can gain more weight up front quicker. So if I go from a 100gr to 125gr, obviously gaining 25 grains, I'm still 50gr less than adding a 75gr. brass insert and I still have the ability to add the 125gr head. The second thing is that there are lots of broadheads that are made only in 100gr. models and not 125's, even if they are made, often times they aren't as readily available.
     
  17. Marauder

    Marauder Die Hard Bowhunter

    Joined:
    Aug 29, 2011
    Posts:
    1,973
    Likes Received:
    55
    Dislikes Received:
    0
    Location:
    Tomahawk, WI
    I would definitely agree with you on all of your points. By adding a little more weight up front that increases your percentage of FOC which many say is better. If I went to a FMJ 300 spine (which I'm thinking about, because of the upgrade of bow), with a 75 grain brass insert, BAR of 10ish grains, a 100 grain BH, and a 30 inch draw, my arrow is going to be pretty heavy. I'm guessing up to 550 grains. That might be overkill for whitetails.
     
  18. Dubbya

    Dubbya Moderator

    Joined:
    Jul 24, 2008
    Posts:
    3,878
    Likes Received:
    26
    Dislikes Received:
    0
    Location:
    Somewhere in, Wyoming

    It could be... but really even if you drop 75 grains, you're going to pick up 25fps. Truly, what difference does that make? Little to none in regards to an animal jumping string, and if your arrow is going to hit where your pin is at, it doesn't really matter how large your pin gap is. If you're shooting a single pin there isn't even a gap to worry about. In the even that you shoot a deer in the shoulder, I promise you'd be happy you had the extra weight than the speed.

    I always build my setups for the worst possible scenario. More deer are shot too far back, than are hit in the shoulder. Most likely because deer are never walking backwards and never back up when the bow goes off. So, the bigger the hole and more tissue damage you can have on a poor shot.... the better off you are. Big mechanicals create bigger holes and more tissue damage but big mechanicals need more momentum and momentum comes from weight, not speed.
     

Share This Page