A more thorough explanation:

A dynamite charge is a set of instructions given to a hung jury to encourage them to reach a verdict. It is also known as allen, nitroglycerin, shotgun, or third-degree charges.

The instructions are controversial because they can pressure jurors to change their opinions and cave to peer pressure, especially minority opinions. Some states do not allow dynamite charges, but Federal courts may use them.

Here is an example of a model dynamite charge from the Ninth Circuit:

Members of the jury, you have reported that you have been unable to reach a unanimous verdict in this case. I have decided to suggest a few additional thoughts to you.

As jurors, you have a duty to discuss the case with one another and to deliberate in an effort to reach a unanimous verdict if each of you can do so without violating your individual judgment and conscience. Each of you must decide the case for yourself, but only after you consider the evidence impartially with your fellow jurors. During your deliberations, you should not hesitate to reexamine your own views and change your opinion if you become persuaded that it is wrong. You should not, however, change an honest belief as to the weight or effect of the evidence solely because of the opinions of your fellow jurors or for the mere purpose of returning a verdict.

I also remind you that in your deliberations you are to consider the instructions that I have given you as a whole. You should not single out any part of any instruction, including this one, and ignore others. They are all equally important.

What I have just said is not meant to rush you or pressure you into agreeing on a verdict. Take as much time as you need to discuss things. There is no hurry.

I ask that you now return to the jury room and continue your deliberations with these additional comments in mind.

This example shows how a judge may give instructions to a hung jury to encourage them to continue deliberating and reach a verdict. The instructions emphasize the importance of impartial consideration of evidence and individual judgment, while also reminding jurors to consider the instructions as a whole and not feel pressured to agree on a verdict.