I have heard that one needs to use mechanicals and not broadheads if your bow shoots over 270 feet per second. The reason I've been told is because the broadheads won't fly right at speeds over 270 FPS. Is that true?

NO

Not at all!!! Lots of misinformation out there on Archery. Especially on the Web.

I shot Muzzy's with my Matthew Compouds for years at over 300 fps.

Then I switched to Rage two blade Mechanicals for a few years, but had problems with them not opening all the time upon Contact.

Now I'm shooting Slick Tricks & Grizz Trick Broadheads exclusively on my Compounds & LongBows. They fly as accurate and as true as field tips,
And they are Deer & Hog killing SOB's ! I'll never go back to Mechanicals.

How far out can you shoot them accurately?

As far as your field tips. If they aren't as accurate the bow or spine is out of tune.

Now there was a time when carbons became popular, bow speeds were increasing and broadheads weren't designed for optimum flight for those conditions... mechanicals flew better... that was in the 90s.

Kent

Up to 60 yards with my Matthews Compound Bow.

Fixed blades from a properly tuned bow will fly accurately as far as you can accurately shoot. I bareshaft tune for perfect arrow flight. That way there are no excuses

OR an arrow with a crooked insert, leading to a broadhead that wobbles in flight. Spin test arrows with broadheads to insure that they spin true.

Not anymore, maybe five years ago, or bit more...about any new design is engineered for the speed of modern bows

I would recommend numbering your arrows on the vanes. If you have an arrow that is outside the group, you can eliminate if it's your form, or a problem with the arrow or the broadhead.

I used to shoot G-5 Montecs, and had one arrow out of a group that was consistantly 2-4 inches outside of the rest. I typically use dinged or dulled G-5s as practice heads, in this case, the tip of the broad head on the "flier" had a pretty decent nick that I had smoothed out, but it was still enough to deflect the arrow away from the rest. The problem disappeared as soon as I tossed the damaged head. I would not have found it as quick without the numbers and seeing the same arrow as the flier.

If you are going to use an old set of Rocky Mountain Razors, or a Fred Bear Razorheads, you may have an issue.

Inconsistent spine can cause a bit of accuracy issues with fixed heads as well. Most of the newer heads fly well at higher speed, but there are still a good many out there that don't fly well at high speed. Many still require a perfectly tuned set-up and concentric shaft to insert as well. For an easy understanding, broadheads such as Slick Trick, Shuttle T, Ramcat, etc tend to fly much better with slightly out of whack set-ups than say a TH or Muzzy. It's always a good idea to check POI and accuracy with your broadheads and the arrows you intend to hunt with.

Professional archer Randy Ulmer wrote about this in a recent article in this month's issue of one of the bowhunting magazines (don't remember which one, as I'm not home right now). Although he himself is a "shooting machine," he said he tested a wide variety of both fixed and mechanical heads shot through a perfectly tuned bow in a shooting machine. He reported that he found through this testing that none of the fixed blade heads will group quite as tightly as the better mechanical heads, regardless of what the manufacturers tell you. The reason: even in very slight breeze, the fixed blade heads will plane and drift some. Plus, fixed blade heads always require larger fletching to stabilize the arrow. Included in the article was a photo of a group he shot at 100 yds with mechanical broadheads, which looked to be about 1.5 MOA with 5-6 arrows!

Speaking from my own experience, I've had some of the low profile fixed blade heads group very well, but I've never gotten them to group as tightly as field points on the same arrows, out of the same bow. I have had mechanicals group just as well as the field points.

Sounds like the broadheads have lousy BC's.

It's that pesky wind again.

Who shoots 'groups' with broadheads, just the thought of cutting fletchings will make you flinch.

Kent

Tune your bow correctly and you don't have to worry about it. I tune bareshaft and can shoot fp, slick tric, rage, Grave diggers to same POI at 40 yds.

Mechanicals ARE broadheads. Aside from that error you got some very bad info. Speed has little to do with what type of broadhead you can use. Spine and tune and FOc play a far bigger role than raw speed does in regards to long range accuracy.

Not to mention that when hunting, you're not shooting groups, nor are you shooting 100 yards.

Very true. However, the point of my post was simply that even if your bow is perfectly tuned, fixed blade broadheads aren't quite as accurate as mechanical broadheads. If there is any wind at all, fixed blade heads will plane more due to much more exposed blade surface area, and wind is a constant factor when hunting, especially in the west.

Randy Ulmer used the 100 yard broadhead group photo because he was competing in a broadhead shooting tournament, using all hunting gear, and it was relevant to his comments about fixed vs. mechanical accuracy. Incidentally, the article is in the July/Aug 2014 issue of Bow and Arrow Hunting, Page 31 & 32.

Ulmer's quote:
"I'm not a big an of most mechanical broadheads. However, I am a big fan of a limited selection of mechanical heads. The reason is simple. They are much more accurate than a fixed head, period. I have spent hundreds of hours grouping and testing broadheads and arrows. I have two shooting machines, so I know this is true. Fixed blade heads do not group as well as mechanicals. None of them do, no matter what the manufacturer says."

By the way, I usually hunt with fixed blade broadheads because I trust them more, but I do acknowledge that, at best, I can get them to shoot almost as well as mechanicals.

Well if that is the case, I take it then that some mechanical's are more consistent in accuracy over others? I have heard that some maybe accurate but not as consistent to open up too and I see that as a big consideration. Wonder if there is a good mechanical broadhead that does both? Although that question maybe like asking what is better a Ford, Mopar or Chevy! LOL